UNIVERSITY  OF  CALIFORNIA 

MEDICAL  CENTER  LIBRARY 

SAN  FRANCISCO 


Gift  of 
Mrs.  Arthur  ?.  Kaelber 


SURGICAL   ANATOMY 


SURGICAL  ANATOMY 


BY 

JOHN    A.    C. ;  MACEWEN 

B.Sc.   IN  ANATOMY  AND  PHYSIOLOGY  WITH  HONOURS 

M.B.,  C.M.  WITH  HONOURS 
FELLOW  OF  THE  FACULTY  OF  PHYSICIANS  AND  SURGEONS,  GLASGOW 

SENIOR    ASSISTANT    TO   THE    REGIUS    PROFESSOR   OF    SURGERY,  GLASGOW  UNIVERSITY ; 

SURGEON     TO     THE     ELDER     HOSPITAL,     GOVAN  ;     ASSISTANT     SURGEON     TO     THE 

ROYAL    INFIRMARY,    GLASGOW,    AND    TO    H.R.H.    PRINCESS    LOUISE   HOSPITAL, 

ROSENEATH  ;    LATE    CIVIL    SURGEON,     SOUTH     AFRICAN     FIELD    FORCE 


NEW     YORK 
WILLIAM     WOOD     &     COMPANY 

MDCCCCX 


PREFACE 

THE  author's  aim  has  been  to  present  a  concise  yet  connected 
account  of  the  anatomical  facts  of  importance  to  the  surgeon, 
indicating  the  relative  importance  of  these  facts  by  brief 
references  to  their  surgical  bearing.  The  physiology  of  the 
parts  under  discussion  has  also  been  touched  upon  when  of 
surgical  import. 

It  is  hoped  that  the  aim  will  commend  itself  to  medical  men, 
and  to  students  of  surgery  and  of  anatomy,  and  that  they  will 
find  the  detail  given  sufficient  to  obviate  frequent  reference 
to  systematic  text-books  of  anatomy. 

Generally,  the  author  has  followed  the  teaching  of  the 
standard  British  and  Continental  works,  and  to  these  he 
gladly  acknowledges  his  indebtedness.  On  a  number  of 
points,  however — as,  for  example,  regarding  the  function  of 
the  periosteum — he  has  followed  that  of  his  teacher,  Sir 
William  Macewen,  whose  opinions  are  based  not  merely  upon 
clinical  experience,  but  also  in  many  cases  upon  long  series  of 
experiments. 

In  the  mode  of  presenting  certain  facts,  likewise — as  in 
surveying  the  anatomy  of  hernia  from  the  abdominal  instead 
of  from  the  external  surface-  -the  author  has  followed 
methods  which  long  experience  in^teaching  has  convinced 
him  are  most  readily  grasped  by  the  student. 

J.  A.  C.  M. 

GLASGOW, 

November  i,  1909. 


132838 


CONTENTS 

SECTION   I 
HEAD  AND  NECK,  VERTEBRAL  COLUMN,  BRAIN 


ERRATA 

Page  212  :  For  '  Freitz  '  read  '  Treitz.' 

289,  line  18  :  For  '  obturator  externus  muscle  '  read  '  obturator 

internus  muscle.' 
,,      312,  line  3  :  For  'bturator  '  read  '  obturator. 


THE    VERTEBRAL    COLUMN  -  139 

THE    CORD           -  -  143 

SECTION  II 
THORAX 

THE    THORAX  -  150 

THE    MAMMARY    GLAND  -  I  56 

THE    THORACIC    CAVITY  -  160 

THE    HEART       -  -  164 

THE    THORACIC    AORTA  -                  -                  -  166 

THE    THORACIC    TRACHEA  -  168 

THE    LUNGS  -  1/2 

THE    OZSOPHAGUS  -  1/4 


CONTENTS 


SECTION   I 

HEAD  AND  NECK,  VERTEBRAL  COLUMN,  BRAIN 
AND  SPINAL  CORD 

PAGE 

THE    HEAD  I 

THE    CRANIUM  5 

THE    BRAIN                                      .  -          IQ 

THE    CRANIAL    NERVES  -          35 

THE    EAR  -         42 

THE  EYE  AND  OCULAR  APPARATUS   -  -    54 

THE  NOSE     -  74 

THE  ACCESSORY  SINUSES  -    80 

THE  FACE     -  85 

THE    UPPER    JAW                      -  -          88 

THE    PAROTID    REGION  -          8p 

THE    LOWER    JAW                                        -  -          92 

THE    TEETH  -         94 

THE    PTERYGO-MAXILLARY  OR  ZYGOMATIC  FOSSA  -  96 

THE    SPHENO-MAXILLARY    FOSSA    -  -          99 

THE    CAVITY    OF    THE    MOUTH           -  IOO 

THE    PHARYNX  -       IO9 

THE    NECK  -       112 

THE    VERTEBRAL    COLUMN  -       139 

THE    CORD  143 

SECTION  II 
THORAX 

THE    THORAX  -       150 

THE    MAMMARY    GLAND  156 

THE    THORACIC    CAVITY  -        l6o 

THE    HEART  -        164 

THE    THORACIC    AORTA  l66 

THE    THORACIC    TRACHEA  -       l68 

THE    LUNGS  -       1/2 

THE    CESOPHAGUS  1/4 


viii  CONTENTS 

SECTION  III 

ABDOMEN  AND  PELVIS 

PAGE 

THE    ABDOMEN            -  \JJ 

THE    ABDOMINAL    PARIETES        -  177 

THE    INGUINAL    REGION      -  187 

THE    ABDOMINAL    CAVITY  2OO 

THE    STOMACH          -  2O3 

THE    DUODENUM  2IO 

THE    SMALL    IN1ESTINE       -  214 

THE    LARGE    INTESTINE C^CUM  217 

THE    VERMIFORM    APPENDIX  2l8 

THE    COLON  222 

THE    LIVER  -       227 

THE    PANCREAS       -  235 

THE    SPLEEN  237 

THE    LUMBAR    REGION  239 

THE    KIDNEYS          -  242 

THE    SUPRARENAL    CAPSULES  -                                                                 246 

THE    SOLAR    PLEXUS  248 

THE    AORTA  248 

THE    INFERIOR    VENA    CAVA  248 

THE    THORACIC    DUCT           -  249 

THE    PELVIS  249 

THE    BLADDER  257 

THE    URETHRA  262 

MALE    ORGANS    OF    GENERATION  265 

THE    PENIS  265 

THE  PROSTATE   -  267 

THE  TESTICLE    -  27! 

FEMALE  ORGANS  OF  GENERATION  275 

THE  UTERUS  275 

THE  VAGINA  277 

THE  OVARY  -   28 1 

THE  VULVA  284 

THE  PERINEUM   -  284 

THE  RECTUM     ------   290 


SECTION   IV 
LOWER  EXTREMITY 

THE    HIP  299 

THE    HIP-JOINT           -  312 

THE    THIGH  -       322 

THE    FEMUR                   -  -       325 


CONTENTS  ix 

PAGE 

THE    KNEE   V  -       328 

THE    KNEE-JOINT     -  334 

THE    LEG  345 

BONES    OF    THE    LEG  -       351 

THE    ANKLE    AND    FOOT  -       353 

THE    ANKLE-JOINT  361 

THE    NERVES    OF    THE    LOWER    EXTREMITY  371 


SECTION   V 
UPPER  EXTREMITY 

REGION    OF    THE    SHOULDER  375 

THE    SHOULDER-JOINT  383 

THE    AXILLA  -       388 

THE    ARM  -       394 

THE    HUMERUS  399 

THE    ELBOW  -       404 

THE    ELBOW-JOINT  -       408 

THE    FOREARM  413 

THE    WRIST    AND    HAND  421 

THE    WRIST-JOINT  -       432 

THE    THUMB    AND    FINGERS  -       436 

THE    NERVES    OF    THE    UPPER  EXTREMITY                                                                     438 

INDEX                                                    -  -       443 


LIST  OF   ILLUSTRATIONS 


FIG.  PAGE 

1.  CRANIAL    POINTS  2 

2.  SCALP    SECTION  6 

3.  CORONAL    HEAD    SECTION    PASSING    THROUGH    PORTION   OF    THE 

SPINAL  CANAL  15 

4.  CORONAL    HEAD    SECTION    PASSING    THROUGH    MIDDLE    EAR  40 

5.  TEMPORAL    BONE  44 

6.  SAGITTAL    HEAD     SECTION    PASSING     THROUGH     THE     TYMPANIC 

MEMBRANE  AND  DISPLAYING  THE  MIDDLE  EAR,  ATTIC, 
ITER,  AND  MASTOID  ANTRUM  -  46 

7.  HORIZONTAL    HEAD    SECTION,    PASSING    THROUGH    THE    MIDDLE 

EAR.       VIEWED    FROM    BELOW  49 

7A.    HORIZONTAL    HEAD    SECTION,    ABOUT    f  INCH    BELOW    FlG.    7           50 

8.  DIAGRAM    OF    EYE  -          63 

9.  DIAGRAM    OF    NASAL    CAVITY,    ETC.    .       -  -          79 

10.  THE    ZYGOMATIC    AND    SPHENO-MAXILLARY    FOSSJE  -          96 

11.  DEEP  DISSECTION   OF  THE  LEFT  SIDE  OF  THE  NECK         -  -US 

12.  DIAGRAM    OF    A    TRANSVERSE    SECTION    OF    THE    NECK    AT    THE 

^  LEVEL  OF  THE  SEVENTH  CERVICAL  VERTEBRA,  SHOWING  THE 
ARRANGEMENT  OF  THE  DEEP  CERVICAL  FASCIA,  AND  THE 
POSITIONS  OF  OTHER  STRUCTURES  -  -  Il8 

13.  DEEP   DISSECTION   OF   THE   LEFT   SUBMAXILLARY    REGION  -       121 

14.  DISSECTION  OF  THE  FRONT  OF  THE    NECK  129 

15.  THE    TERMINAL    PART    OF    THE    SPINAL    CORD,    AND    THE    CAUDA 

EQUINA  144 

1 6.  THE   APPROXIMATE   RELATION   TO   THE   SPINAL   NERVES   OF  THE 

VARIOUS  MOTOR,  SENSORY,  AND  REFLEX  FUNCTIONS  OF  THE 
SPINAL  CORD  -  147 

17.  DIAGRAM  OF  BREAST  LYMPHATICS  -       158 
1 8'.    TRANSVERSE  SECTION   OF   THE   THORAX   THROUGH   THE   SECOND 

STERNEBRA  IN  FRONT  AND  THE  BODY  OF  THE  NINTH 
THORACIC  VERTEBRA  BEHIND,  SHOWING  THE  REFLECTIONS 
OF  THE  PLEURAE  AND  THE  POSITION  OF  THE  VISCERA  -  1 62 

19.  SCHEME    OF    ABDOMINAL    MUSCLES    (IN    SECTION)  -       l8l 

20.  CUTANEOUS  NERVES  OF  THE  TRUNK.       ANTERO-LATERAL  VIEW  -       184 

21.  STEREOGRAM   OF  ABDOMINAL  WALL,    GIVING   AN   EXAGGERATED 

VIEW  OF  THE  INGUINAL,  FEMORAL,  AND  OBTURATOR  CANALS-       I  88 

xi 


xii  LIST  OF  ILLUSTRATIONS 

FIG.  PAGE 

22.  DIAGRAM    OF    ABDOMINAL    WALL    FROM    BEHIND  -       IQ2 

23.  DIAGRAM    ILLUSTRATING  THE    DEVELOPMENTAL    OBLITERATION 

OF  THE  FUNICULAR  PROCESS  (SERIES  A),  AND  THE  FORMS  OF 
INGUINAL  HERNIA  (SERIES  B),  AND  HYDROCELE  (SERIES  C) 
WHICH  MAY  ARISE  THEREFROM  196 

24.  DIAGRAM    OF    PERITONEUM,    ITS    SACS    AND    FOLDS  2O2 

25.  THE    SUPRAMESOCOLIC       COMPARTMENT       OF       THE       ABDOMEN. 

PORTIONS  OF  STOMACH  AND  LIVER  HAVE  BEEN  REMOVED  TO 
DISPLAY  THE  DIAPHRAGM  FORMED  BY  THE  TRANSVERSE 
COLON  AND  MESOCOLON  WITH  KIDNEY,  SPLEEN,  AND 
PANCREAS  204 

26.  TRANSVERSE  SECTION  OF  THE  ABDOMEN  AT  THE  LEVEL  OF  THE 

FIRST    LUMBAR    VERTEBRA  2IO 

27.  THE    INFRAMESOCOLIC    COMPARTMENT    OF    THE    ABDOMEN.       ON 

THE  RIGHT  A  PORTION  OF  STOMACH,  AND  TRANSVERSE 
COLON  CARRYING  WITH  IT  TRANSVERSE  MESOCOLON,  ARE 
SHOWN  TURNED  UP  AS  FOR  THE  OPERATION  FOR  POSTERIOR 
GASTRO-JEJUNOSTOMY  212 

28.  THE    INFERIOR    SURFACE    OF    THE    LIVER  -       229 

29.  ANTERIOR    VERTICAL    SECTION    OF    PELVIS    FROM    FRONT  252 

30.  POSTERIOR    VERTICAL    SECTION    OF    PELVIS    FROM    BEHIND  254 

31.  VIEW    OF    PELVIC    BASIN    FROM    ABOVE  255 

32.  DIAGRAM    OF    MALE    PELVIS.       VIEWED    FROM    ABOVE.       ON    THE 

RIGHT  SIDE  THE  PERITONEUM  HAS  BEEN  FOLDED  OVER,  DIS- 
PLAYING THE  RIDGES  AND  FOSSAE,  WHILE  ON  THE  LEFT  THE 
PELVIS  IS  SHOWN  CUT  IN  SECTION  -  258 

33.  THE    VISCERA    OF    THE    MALE    PELVIS    (LATERAL    VIEW)  2/O 

34.  VIEW    OF    FEMALE    PELVIC    BASIN    FROM    ABOVE  -*    2/8 

35.  THE     GLUTEAL     REGION     AND     BACK     OF     THE     THIGH.        DEEP 

DISSECTION  303 

36.  THE    FRONT    OF    THE    THIGH    (SCARPA'S    TRIANGLE)  307 

37.  OUTLINE    DIAGRAM    OF    LONGITUDINAL    SECTION    OF    HIP  313 

38.  OUTLINE    DIAGRAM    OF    TRANSVERSE  SECTION  OF  THIGH  AT  THE 

JUNCTION  OF  UPPER  AND  MIDDLE  THIRDS  324 

39.  SAGITTAL  SECTION   OF   THE   RIGHT   KNEE-JOINT,    VIEWED   FROM 

THE    OUTER    SIDE  336 

40.  DIAGRAM    OF    KNEE-JOINT    OF    ADOLESCENT  34O 

41.  OUTLINE    DIAGRAM    OF    TRANSVERSE    SECTION    OF    LEG    IN    THE 

UPPER    THIRD  348 

42.  OUTLINE  DIAGRAM  OF  LONGITUDINAL  SECTION   OF  FOOT  356 

43.  THE    SYNOVIAL    SHEATHS    AT    THE    ANKLE.       ANTERIOR    VIEW    -  359 

44.  THE    SYNOVIAL    SHEATHS    AT    THE    ANKLE.       INTERNAL    VIEW    -  360 

45.  DIAGRAM    OF    THE    SIX    SYNOVIAL    MEMBRANES    OF    THE    FOOT   -  365 

46.  NERVE-SUPPLY    OF    LOWER    EXTREMITY  373 

47.  THE  RIGHT  GLENOID  CAVITY,   AND  THE  ADJACENT  LIGAMENTS  -  384 

48.  COSTO-CORACOID    MEMBRANE  389 


LIST  OF  ILLUSTRATIONS  xiii 

FIG.                        4  PAGE 

49.  OUTLINE    DIAGRAM    OF    TRANSVERSE    SECTION    OF    UPPER    ARM 

IN   THE   MIDDLE   THIRD  403 

50.  THE    AXILLARY  SPACE,   AFTER  REFLECTION  OF  THE  PECTORALIS 

MAJOR  ;  AND  THE  SUBCLAVIAN  TRIANGLE  404 

51.  SUPERFICIAL  DISSECTION  OF  THE  FRONT  OF  THE  LEFT  ELBOW  -  406 

52.  OUTLINE    DIAGRAM    OF    TRANSVERSE    SECTION    OF    ELBOW  408 

53.  LONGITUDINAL    SECTION    OF    ELBOW       -                                                         -  4!  I 

54.  LONGITUDINAL    SECTION    OF    FOREARM    AND    HAND                              -  41? 

55.  OUTLINE    DIAGRAM    OF    TRANSVERSE    SECTION    OF    FOREARM    IN 

LOWER  THIRD                                                                                                                -  418 

56.  DEEP   DISSECTION   OF  FRONT   OF   RIGHT   FOREARM,    AND   SUPER- 

FICIAL   DISSECTION    OF    PALM  424 

57.  THE    GREAT    PALMAR    BURS  A,    AND    THE       SYNOVIAL       SHEATHS 

OF    THE    FLEXOR    TENDONS  429 

58.  THE    SYNOVIAL    SHEATHS    OF    THE    EXTENSOR    TENDONS  432 

59.  DIAGRAM  OF  THE  FIVE  SYNOVIAL  MEMBRANES   OF  THE   HAND  -  433 

60.  TRANSVERSE    SECTION    OF    WRIST  435 

61.  CUTANEOUS    NERVES    OF    ARM                                                                                 -  440 


SURGICAL  ANATOMY 


SECTION  I 

HEAD  AND  NECK,  VERTEBRAL  COLUMN, 
BRAIN  AND  SPINAL  CORD 

THE    HEAD 

Surface  Anatomy. 

THE  head  is  generally  not  symmetrical,  the  left  half  being  the 
larger.  In  some  cases  this  asymmetry  is  due  to  pressure  at 
birth,  rickets,  or  syphilis,  and  is  very  marked,  the  head  pre- 
senting a  lop-sided  appearance.  The  relation  of  length  to 
breadth  of  the  skull  varies  considerably  in  different  races, 
the  term  dolichocephalic  denoting  an  elongated  type,  and 
br  achy  cephalic  one  which  is  more  rounded.  The  cranial 
capacity  likewise  varies,  being  small  (microcephalic)  in  African 
Bushmen,  and  large  (megacephalic)  in  more  civilized  races. 
A  microcephalic  condition  is  met  with  pathologically  asso- 
ciated with  cretinoid  idiocy,  while  in  hydrocephalus  the  head 
is  often  very  large. 

It  must  not  be  concluded  that  the  shape  of  the  head  is 
always  an  index  of  the  cranial  development,  and  this  is  par- 
ticularly the  case  in  the  frontal  region,  where  the  '  develop- 
ment '  depends  largely  upon  the  presence  and  size  of  the  frontal 
sinuses.  A  high  and  prominent  forehead  is  frequently 
associated  with  rickets,  in  which  the  frontal  and  parietal 
eminences  may  also  be  enlarged  owing  to  new  bone  formation. 
Inherited  syphilis  also  produces  overgrowths  of  bone  round 

i 


2  SURGICAL  ANATOMY 

the  anterior  fontanelle,  constituting  what  are  known  as 
Parrot's  nodes. 

The  sagittal  suture  is  that  formed  by  the  union  of  the 
superior  margins  of  the  parietal  bones.  It  can  generally 
be  detected  by  palpation  running  antero-posteriorly.  By 
a  SAGITTAL  SECTION  is  meant  one  running  antero-posteriorly. 

The  junction  of  the  parietals  anteriorly  with  the  frontal 
bones  forms  the  coronal  suture,  which  can  also  generally  be 
palpated,  running  across  the  vertex  from  side  to  side.  By  a 


FIG.  i. — CRANIAL  POINTS. 

1.  Nasion.  5.  Obelion.  9.  Stephanion. 

2.  Glabella.  6.   Lambda.  10.  Meatal  Point. 

3.  Ophyron.  7.   Inion.  n.  Pre-auricular  point. 

4.  Bregma.  8.  Pterion.  12.  Asterion. 

CORONAL  SECTION  is  meant  one  running  at  right  angles  to  the 
sagittal. 

The  point  at  which  coronal  and  sagittal  sutures  meet  is 
called  the  BREGMA,  and  can  be  made  out  on  careful  palpation. 
It  can  be  indicated  approximately  by  taking  the  mid  point 
of  a  line  drawn  across  the  vertex  from  the  centre  of  one  ex- 
ternal auditory  meatus  to  the  other. 

Posteriorly  the  parietals  form  with  the  occipital  bone  the 
lambdoidal  suture,  the  apex  of  which  is  called  the  LAMBDA. 
It  is  generally  palpable,  but  its  exact  position  may  be  difficult 
to  define,  owing  to  the  frequent  presence  of  a  large  Wormian 


THE  HEAD  3 

bone  at*' this  point,  called  the  cs  cpactal  or  preinter  parietal 
bone.  The  lambda  lies  about  2j  inches  above  the  external 
occipital  protuberance,  and  indicates  the  position  of  the 
posterior  fontanelle.  When  the  os  epactal  is  present,  its 
lower  border  indicates  fairly  exactly  the  most  prominent 
part  of  the  skull  posteriorly. 

The  external  occipital  protuberance  is  called  the  IN  ION, 
and  it  should  be  noted  that  it  does  not  form  the  most  prominent 
point  of  the  skull  posteriorly,  but  lies  distinctly  below  that 
point. 

The  middle  of  the  fronto-nasal  suture  is  called  the  NASION, 
and  is  easily  located  at  the  root  of  the  nose.  The  point  of 
articulation  of  the  antero-inferior  angle  of  the  parietal  with  the 
sphenoid  is  called  the  PTERION,  and  is  indicated  by  taking  a 
point  i  J  inches  behind  and  J  inch  above  the  most  prominent 
point  of  the  external  angular  process  of  the  frontal.  The 
frontal  and  temporal  bones  also  articulate  here,  the  sutures 
forming  together  a  rough  capital  H.  The  MEATAL  or  AURICU- 
LAR POINT  is  the  centre  of  the  external  auditory  meatus.  The 
PREAURICULAR  POINT  is  situated  immediately  above  the 
zygoma  and  in  front  of  the  tragus. 

The  point  of  junction  of  parietal,  mastoid,  and  occipital 
bones  is  called  the  ASTERION,  and  lies  ij  inches  behind  and 
i  inch  above  the  auricular  point. 

The  GLABELLA  is  a  point  midway  between  the  two  super- 
ciliary ridges,  and  the  VERTEX  is  the  summit  of  the  cranial 
vault — a  variable  point. 

In  addition  to  the  normal  cranial  sutures,  a  festal  suture 
may  persist,  and  cause  error  in  diagnosis.  The  most  common 
of  these  is  one  extending  up  from  the  foramen  magnum 
toward  the  external  occipital  protuberance,  which  normally 
is  closed  by  the  fifth  month  of  intra-uterine  life.  This  is  the 
most  common  site  of  cranial  meningocele,  or  protrusion  of  the 
cerebral  membranes,  the  next  most  common  position  being 
through  the  fronto-nasal  suture.  In  addition  to  the  occipital 
suture  mentioned,  which  may  extend  through  the  whole 
length  of  the  occiput,  the  expanded  portion  of  the  occiput 
is  divided  into  four  pieces  at  birth  by  two  lateral  fissures 
running  into  the  protuberance.  These  may  persist  and  be 
mistaken  for  fractures,  and  it  is  well  to  remember  that  the 
portion  of  occiput  above  these  fissures  is  developed  from 

I — 2 


4  SURGICAL  ANATOMY 

membrane,  and  the  portion  below  from  cartilage.  Fissures 
may  also  persist  in  the  posterior  portions  of  the  parietals  (the 
small  portion  of  the  parietal  bone  so  separated  being  called 
an  interparietal  bone),  and  if  bilateral  and  joined  may  present 
a  sagittal  fontanelle. 

Of  much  importance  to  the  surgeon  is  the  power  of  locating 
the  principal  cerebral  centres  and  bloodvessels  by  means  of 
external  measurements.  A  simple  method  of  locating  the 
Rolandic  fissure,  around  which  the  chief  motor  areas  are 
grouped,  is  to  take  a  point  J  inch  behind  the  mid-point 
between  nasion  and  inion,  and  from  it  draw  a  line  down  and 
forwards  at  an  angle  of  67^  degrees  (three-quarters  of  a  right 
angle)  till  it  meets  the  Sylvian  fissure.  The  position  of  the 
Sylvian  fissure  is  indicated  by  drawing  a  line  upwards  and 
backwards  from  the  pterion  to  a  point  f  inch  below  the 
parietal  eminence,  and  the  parietal  eminence  lies  at  the  junc- 
tion of  the  upper  and  middle  thirds  of  a  line  drawn  from  a 
point  \  inch  behind  the  mid-point  between  nasion  and  inion 
to  the  auricular  point.  The  short  ascending  limb  of  the  Sylvian 
fissure  is  indicated  by  a  line  f  inch  long,  running  upwards  and 
slightly  forwards  from  the  pterion.  A  line  drawn  from  the 
nasion  to  the  inion  gives  the  position  of  the  longitudinal 
fissure  of  the  brain.  The  longitudinal  sinus  runs  along  this 
line,  slightly  to  the  right  side.  The  lateral  sinus  is  represented 
by  a  line  drawn  from  a  point  J  inch  above  the  inion  to  the 
asterion.  At  this  point  the  lateral  sinus  turns  rather  sharply 
down  and  forwards,  forming  the  commencement  of  the  sigmoid 
sinus,  which  is  very  variable  in  its  exact  position.  In  some 
cases  the  knee  of  the  sinus  comes  to  within  J-  inch  of  the 
external  osseous  meatus,  while  in  others  it  may  be  f  inch 
behind  it. 

The  trunk  of  the  middle  meningeal  artery  may  be  reached 
at  a  point  ij  inches  behind  the  external  angular  process  of 
the  frontal,  and  f  inch  above  the  zygoma,  while  its  anterior 
branch  is  reached  at  a  point  f  inch  higher  up. 

The  supra-orbital  notch  lies  at  the  junction  of  the  middle 
and  inner  thirds  of  the  supra-orbital  ridge,  and  is  generally 
easily  palpable.  A  line  drawn  down  and  outwards  from  it 
to  the  interval  between  the  two  bicuspid  teeth  of  both  jaws 
passes  through  the  infra-orbital  foramen,  which  is  situated 
J  inch  below  the  lower  margin  of  the  orbit,  and,  if  prolonged, 


THE  HEAD  5 

indicate*'  the  position  of  the  mental  foramen,  situated  midway 
between  the  upper  and  lower  borders  of  the  ramus  of  the 
lower  jaw.  The  position  of  the  point  of  entrance  of  the 
inferior  dental  nerve  into  its  canal  on  the  inner  side  of  the 
ramus  of  the  lower  jaw  is  got  by  taking  the  mid-point  between 
zygoma  and  inferior  border  of  lower  jaw,  and  the  mid  point 
between  anterior  and  posterior  borders  of  the  ascending 
ramus. 

The  facial  artery  crosses  the  lower  jaw  about  J  inch  in  front 
of  the  angle,  at  which  point  there  is  generally  a  slight  depres- 
sion in  the  bone,  which  forms  the  best  guide  to  the  vessel. 

THE  CRANIUM. 

The  scalp  consists  of  the  skin  of  the  head,  subcutaneous 
tissues,  and  occipito-frontalis  muscle,  these  structures  being 
intimately  attached  to  one  another  by  large  numbers  of  small 
fibrous  bands.  The  boundaries  of  the  true  scalp  are,  therefore, 
those  of  the  occipito-frontalis  muscle,  which  may  be  indicated 
on  the  surface  by  a  line  running  from  the  middle  point  in 
front  along  the  supra-orbital  margin  to  the  angular  process 
of  the  frontal,  thence  slightly  above  the  zygoma  to  the 
external  auditory  meatus,  and  so  to  the  superior  curved  line 
of  the  occipital  bone. 

The  succeeding  layers  consist  of — (a)  the  so-called  '  dangerous 
area,'  consisting  of  a  layer  of  loose  areolar  tissue  ;  (b)  the 
pericranium,  or  external  periosteum  of  the  skull  ;  (c)  the  skull 
itself.  The  skin  of  the  scalp  is  very  thick,  particularly  over 
the  occipital  region,  and  is  well  supplied  with  sudoriparous 
and  sebaceous  glands,  the  latter  giving  rise  to  sebaceous  or 
atheromatous  cysts  or  wens  through  blockage  of  their  ducts. 
These  cysts  are  generally  confined  to  the  skin,  not  involving 
the  subcutaneous  structures,  and  in  removing  them  it  is 
important  not  to  open  the  sac,  nor  to  open  into  the  dangerous 
area,  as  the  contents  are  generally  septic. 

Owing  to  the  very  lax  attachment  of  the  occipito-frontalis 
to  the  underlying  pericranium,  or  periosteum  of  the  skull,  by 
loose  areolar  tissue,  it  possesses  a  great  degree  of  mobility, 
as  is  evidenced  by  the  movement  of  the  scalp  as  a  whole 
when  the  brow  is  wrinkled.  This  freedom  of  movement  has 
an  effect  in  protecting  the  scalp  from  injury,  and  the  looseness 


6  SURGICAL  ANATOMY 

of  the  attachment  is  also  illustrated  in  avulsion  of  the  scalp 
from  the  hair  becoming  caught  in  revolving  machinery,  and  in 
scalping. 

The  scalp  has  a  rich  vascular  and  lymphatic  supply.  The 
ARTERIES  run  in  an  upward  direction  in  the  subcutaneous 
tissues,  are  tortuous,  and  anastomose  freely.  They  arise 


FIG.  2. — SCALP  SECTION. 

1.  Scalp,  composed  of  skin,  dense  cellular  tissue,  and  occipito-frontalis  aponeurosis. 

Fluid  accumulations  small  and  circumscribed. 

2.  Loose  areolar  layer.     Fluid  accumulations  widely  spread. 

3.  Pericranium,    loosely   attached   to   bone  save   at   sutures.     Fluid   accumulations 

limited  to  one  bone. 

4.  Bone  of  skull  with  vascular  diploic  tissue. 

5.  Dura  mater,  comparatively  loosely  attached  save   at  sutures.     Fluid  accumula- 

tions may  be  considerable. 

6.  Pia-arachnoid,  loose  but  very  vascular.     Fluid  accumulations  widely  spread. 

7.  Brain  matter  with  small  end  arteries     Fluid  accumulations  generally  circumscribed. 

8.  Superior  longitudinal  sinus,  formed  by  splitting  of  dura,  and  presenting  a  projecting 

Pacchionian  body  which  communicates  between  the  sinus  and  the  subarachnoid 
space,  and  probably  assists  in  regulating  the  amount  of  cerebro-spinal  fluid. 

9.  Falx  cerebri  formed  by  a  process  of  dura. 

from  frontal  and  supra- orbital  branches  of  the  ophthalmic 
of  the  internal  carotid,  and  the  superficial  temporal,  posterior 
auricular  and  occipital  branches  of  the  external  carotid. 

The  superficial  temporal  artery  may  be  reached  through 
a  vertical  incision  |  inch  in  front  of  the  ear,  and  the  occipital, 
which  is  generally  the  largest  vessel  of  the  scalp,  through  an 
incision  passing  obliquely  backwards  and  upwards  from  behind 
the  tip  of  the  mastoid  process. 


THE  HEAD  7 

Ligature  of  these  vessels,  and  particularly  of  the  temporal, 
may  be  required  (apart  from  injuries)  in  the  treatment  of 
cirsoid  aneurysm,  which  sometimes  affects  them.  Owing, 
however,  to  the  free  anastomosis,  this  treatment  is  seldom 
successful.  Where,  from  any  reason,  it  is  desirable  to  check 
the  whole  blood- supply  of  the  scalp  (as  in  operation  on  large 
naevi),  a  piece  of  rubber  tubing  maybe  tied  tightly  round  the 
head  at  the  level  of  the  eyebrows  in  front  and  under  the 
external  occipital  protuberance  behind.  Owing  to  the  upward 
direction  of  the  cranial  vessels,  one  should,  in  cutting  scalp 
flaps,  make  them  with  the  convexity  toward  the  vertex. 
While  the  arteries  are  comparatively  free  in  the  subcutaneous 
tissues,  running  in  tunnelled  spaces,  the  veins  are  rather 
adherent,  and  hence,  when  divided,  tend  to  gape  and  give  rise 
to  free  haemorrhage.  In  operations  on  the  scalp  haemor- 
rhage, as  just  explained,  is  generally  troublesome,  and,  owing 
to  the  very  dense  nature  of  the  scalp  itself,  the  vessels  are 
frequently  difficult  to  pick  up  with  pressure  forceps.  Artery 
forceps  may  be  employed  for  the  more  troublesome  ones,  and 
the  others  arrested  by  firm  pressure  applied  for  a  few  minutes. 

The  extreme  vascularity  of  the  scalp  explains  why  wounds 
heal  so  rapidly,  and  why  sloughing  rarely  occurs,  even  when 
portions  are  almost  detached.  In  one  rhinoplastic  operation 
for  the  formation  of  a  new  nose  a  flap  is  taken  down  from 
the  brow,  the  portion  so  detached  being  fed  through  its 
narrow  pedicle  by  the  small  frontal  artery. 

The  LYMPHATICS  of  a  small  central  anterior  portion  of  the 
brow  and  upper  part  of  the  nose  drain  to  the  submaxillary 
glands  ;  the  frontal  and  parietal  regions  in  front  of  the  ear 
drain  to  the  preauriciilar  ;  the  parietal  region  over  and  for  a 
short  distance  behind  the  ear  drains  to  the  postauricular  ; 
and  the  remainder  to  the  occipital  glands. 

The  NERVES  supplying  the  scalp  are  the  supratrochlear, 
supra-orbital  (which  may  be  cut  for  relief  of  neuralgia  of  scalp), 
auriculo-temporal,  posterior  auricular,  and  great  occipital. 

W^OUNDS  of  the  scalp  do  not  gape,  as  a  rule,  unless  the 
occipito-frontalis  be  divided  in  a  transverse  direction.  They 
frequently  present  a  sharply- cut  appearance,  even  when  pro- 
duced by  blows  from  blunt  instruments,  the  scalp  splitting 
over  the  cranium  as  the  outer  coating  of  a  cricket-ball  some- 
times does  when  struck  by  a  flat  bat.  A  close  inspection  of 


8  SURGICAL  ANATOMY 

such  wounds  produced  by  blunt  instruments  shows  that  llu: 
hair  bulbs  are  not  cut,  but  project  from  one  edge  of  the  wound  ; 
and,  further,  nerve  fibrils,  and  even  vessels,  may  be  seen 
stretching  uncut  across  the  deeper  parts. 

Owing  to  the  dense  structure  of  the  scalp,  large  effusions 
of  fluid,  such  as  pus  or  blood,  cannot  occur  in  it.  In  many 
severe  contusions,  however,  the  scalp  tissues  are  actually  dis- 
placed and  heaped  up  peripherally,  while  a  considerable 
amount  of  blood  is  also  effused.  This  effused  blood  clots  more 
rapidly  at  the  periphery  than  in  the  centre,  and  the  peripheral 
portion  is  frequently  so  firm  and  sharply  defined  that,  on 
running  the  fingers  over  it,  and  then  dipping  into  the  central 
soft  portion,  one  is  apt  to  think  that  a  depressed  fracture  of 
the  skull  has  occurred.  When  in  doubt,  firm  pressure  should 
be  applied  by  the  finger  for  a  short  time  over  the  raised  area. 
If  due  to  blood-clot,  it  will  be  dispersed  by  the  pressure, 
whereas  fracture  is  rendered  more  prominent. 

Effusions  of  fluid  in  the  loose  AREOLAR  TISSUE  lying  under 
the  occipito-frontalis,  on  the  other  hand,  are  only  limited  by 
the  insertions  of  the  occipito-frontalis  muscle  anteriorly  and 
posteriorly,  while  laterally  they  may  extend  downwards  over 
the  temporal  fascia  to  near  the  zygoma.  This  region,  then,  is 
known  as  the  dangerous  area  of  the  scalp,  and  particularly 
where  there  is  reason  to  fear  that  it  has  been  opened  into  by  a 
septic  scalp  wound  should  the  wound  be  treated  by  packing, 
allowing  it  to  granulate  from  the  bottom.  It  should  be 
noted  that  the  occipito-frontalis  is  practically  continuous  in 
front  with  the  pyramidalis  nasi,  corrugator  supercilii,  and 
orbicularis  palpebrarum,  and  hence  effusions  readily  extend 
into  the  tissues  of  the  eyelid  and  nose  from  under  the  occipito- 
frontalis. 

The  PERICRANIUM  forms  a  rather  loose  covering  for  the 
bones  of  the  skull,  save  at  the  sutures,  where  it  dips  in  between 
them  and  is  firmly  adherent.  Effusions  of  fluid  under  the 
pericranium  are  therefore  generally  confined  to  a  single  bone. 

Cephalhczmatoma,  an  effusion  of  blood  under  the  pericranium 
of  the  parietals,  is  generally  due  to  pressure  or  injury  during 
labour  (see  also  Extra-  and  Subdural  Haemorrhage). 

Stripping  of  the  pericranium  is  not  generally  a  matter  of 
much  moment,  as  the  bones  of  the  skull  derive  their  chief 
blood-supply  from  the  diploic  vessels. 


THE  HEAD  9 

Temporal  Region. — Over  the  temporal  region  the  aponeu- 
rosis  of  the  occipito-frontalis  becomes  very  attenuated,  losing 
itself  gradually  as  it  approaches  the  zygoma  by  numerous 
small  insertions  into  the  temporal  fascia.  It  also  sends  some 
prolongations  into  the  subcutaneous  tissues,  but  in  this  region 
the  aponeurosis  is  not  nearly  so  intimately  associated  with 
the  subcutaneous  tissues  as  in  the  scalp  proper. 

The  temporal  muscle  takes  origin  from,  and  is  covered  in  by, 
the  temporal  fascia,  which  arises  from  the  temporal  ridge  and 
runs  down  to  be  inserted  into  the  zygoma,  splitting  as  it 
does  so  to  enclose  branches  of  the  temporal  and  orbital 
arteries,  embedded  in  fat.  The  fascia  is  remarkably  strong  and 
dense,  so  as  to  be  practically  indistinguishable  from  bone  on 
palpation.  Were  an  abscess  occurring  in  the  temporal  region, 
this  fascia  would  tend  to  prevent  its  pointing  locally,  and 
would  direct  it  under  the  zygoma,  whence  it  may  extend  even 
to  the  neck. 

The  pericranium  in  this  region  is  much  more  adherent  than 
it  is  over  the  vault,  and  hence  subpericranial  haematomas  are 
very  unlikely  to  occur. 

The  bones  composing  the  cranial  vault  are  developed  in 
membrane,  possess  few  osteoblasts,  and  have  but  little 
healing  power.  Thus,  after  destruction  of  a  portion  of  the 
vault,  it  is  unusual  to  find  repair  by  osseous  tissue,  the  bone 
generally  being  replaced  by  fibrous  tissue. 

Necrosis  most  often  affects  the  frontal  and  parietal  bones, 
and  not  infrequently  the  external  table  alone  is  affected. 
Extensive  destruction  of  the  anterior  portion  of  the  vault  is 
sometimes  due  to  syphilitic  ulceration,  the  dura  presenting 
at  the  bottom  of  the  ulcer.  Craniotabes  is  a  condition  met 
with  in  early  life,  affecting  generally  the  parieto-occipital 
region,  due  to  rickets  or  inherited  syphilis,  in  which  the  bone 
becomes  thin  and  parchment-like. 

The  inner  table  of  the  skull  is  thinner  and  more  brittle  than 
the  outer,  and  in  fractures  or  gun-shot  wounds  involving  both 
tables  is  generally  much  more  extensively  shattered  than  the 
outer.  In  some  cases  where  a  rifle-bullet  strikes  the  skull 
tangentially,  cutting  a  groove  in  the  external  table,  the  inner, 
although  apparently  not  directly  implicated,  has  been  shat- 
tered over  a  considerable  area  and  driven  into  the  brain 
substance.  Sometimes  also,  as  the  result  of  injury,  the  inner 


io  SURGICAL  ANATOMY 

table  may  be  fractured  without  evidence  of  fracture  affecting 
the  outer  table.  The  inner  table  is  grooved  by  the  sinuses 
and  the  Pacchionian  bodies,  and  also  by  the  middle  meningeal 
artery.  In  some  cases  the  artery  is  actually  embedded  in 
the  bone,  and  is  then  particularly  liable  to  injury  from  fracture. 

The  diploic  tissue  between  the  two  tables  is  very  vas- 
cular, most  of  the  blood  being  derived  from  the  meningeal 
vessels.  The  return  flow  of  venous  blood  is  chiefly  directed 
through  the  diploic  veins  toward  the  great  sinuses,  but  a 
portion  is  carried  by  emissary  veins  to  the  superficial  blood 
channels,  which  thus  bring  superficial  and  deep  systems  into 
direct  communication.  Other  emissary  veins  run  directly 
from  the  sinuses  to  the  superficial  veins. 

These  emissary  veins  are  of  great  importance  surgically, 
as  they  afford  access  for  pyogenic  organisms  to  the  sinuses 
and  meninges  from  superficial  affections  at  these  parts. 
The  most  important  are  :  (a)  Mastoid,  which  runs  from  the 
sigmoid  sinus  to  the  posterior  auricular  or  occipital  veins 
through  the  mastoid  foramen  ;  (b)  parietal,  from  the  superior 
longitudinal  sinus  to  the  scalp  veins  through  the  parietal  fora- 
men ;  (c)  superior  orbital,  communicating  with  the  ophthalmic 
and  facial  frontal  diploic  veins  ;  (d)  vein  of  foramen  caecum, 
connecting  those  of  the  nasal  mucous  membrane  with  superior 
longitudinal  sinus  ;  (e)  veins  from  cavernous  sinus  through  the 
foramen  ovale  ;  (/)  veins  from  the  lateral  sinus  throug  i  the 
postcondylar  foramen,  etc.,  to  deep  occipital  veins  ;  (g)  nu- 
merous small  vessels  running  from  inside  to  outside  of  the 
skull  through  the  sutures  ;  (h)  frontal,  nasal,  and  angular 
veins,  with  the  cavernous  sinus,  through  the  ophthalmic  veins. 

The  skull  varies  greatly  in  thickness — not  only  in  different 
individuals,  but  also  at  different  parts — a  point  which  must 
be  kept  in  mind  when  trephining.  Speaking  generally,  it  is 
thickest  over  the  frontal  and  occipital  regions,  attaining  a 
maximum  at  the  posterior  occipital  protuberance,  and  is 
thinnest  over  the  squamous  portion  of  the  temporal. 

The  frontal  sinuses  are  formed  at  the  expense  of  the  diploic 
tissue,  which  is  absent  at  these  places,  while  the  tables  are 
wide  apart.  They  vary  much  in  size  in  different  individuals, 
and  are  generally  larger  in  males.  The  septum  between  them 
is  frequently  displaced  to  one  side  or  other,  and  sometimes 
only  one  sinus  may  exist,  or  they  may  be  altogether  absent. 


THE  HEAD  11 

They  caja  generally  be  examined  in  a  darkened  room  by 
transillumination  from  a  lamp  in  the  mouth.  When  normal, 
they  are  fairly  translucent,  as  a  rule,  whereas  they  become 
opaque  when  rilled  with  pus. 

The  cranial  sutures  are  of  importance  surgically,  as  their 
arrangement,  interdigitation,  and  complicated  structure,  while 
producing  practically  a  single  bone,  yet  do  much  in  conjunc- 
tion with  the  elasticity  of  the  bones  themselves  to  modify 
fracturing  forces.  At  birth  the  persistence  of  the  anterior 
fontanelle  (which  normally  closes  by  the  second  year)  increases 
the  adaptability  of  the  head.  The  posterior  fontanelle  normally 
closes  before  birth.  Separation  at  the  sutures  rarely  occurs 
apart  from  fracture  save  in  early  youth,  but  a  few  cases  of 
separation  at  the  squamous  suture  have  occurred.  The 
coronal  and  sagittal  sutures  have  been  most  frequently  affected 
by  fracture.  The  skull  also  possesses  a  series  of  buttresses,  by 
which  the  force  of  blows  is  transmitted  and  diffused,  thereby 
minimizing  the  chances  of  fracture.  Sometimes,  however, 
a  blow  struck  upon  a  strong,  unyielding  bone,  such  as  the 
occipital,  may  be  transmitted  to  a  weak  bone — e.g.,  the  orbital 
plate  of  the  frontal — with  such  force  as  to  fracture  it,  the 
bone  struck  remaining  intact  (fracture  by  contre-coup) .  In 
old  persons  the  sutures  tend  to  disappear,  synostosis  occurring, 
while  the  bones  themselves  lose  their  elasticity  to  a  great 
extent,  fracture  of  the  skull  being  then  more  easily  produced. 

The  Wormian  bones,  or  ossa  triquitra,  occur  chiefly  about  the 
lambdoidal  suture.  Generally  few  in  number  and  sym- 
metrical, they  may  form  a  regular  chain,  and  in  cases  of 
hydrocephalus  are  present  in  large  numbers,  and  attain  a 
large  size.  The  os  epactal  at  the  apex  of  the  occipital  has 
already  been  referred  to.  They  are  occasionally  met  with 
about  the  lachrymal  bones  and  outer  extremity  of  the  spheno- 
m axillary  fissure,  and  one  frequently  occurs  about  the  antero- 
inferior  angle  of  the  parietal,  in  the  region  of  the  pterion, 
which  is  called  the  epipteric  bone,  is  scale-like,  and  may  sug- 
gest a  separation  of  the  tip  of  the  great  wing  of  the  sphenoid. 

FRACTURES  OF  THE  VAULT  of  the  skull  are  generally  due  to 
direct  violence.  Where  the  blow  is  struck  on  the  frontal 
region,  the  force  is  transmitted  to  the  parietals  upon  which 
the  posterior  part  of  the  frontal  rests,  and  these  deal  with  it 
as  follows.  When  the  parietal  region  is  injured,  the  force 


12  SURGICAL  ANATOMY 

tends  to  drive  the  upper  borders  of  the  bone  inwards,  and 
therefore  the  lower  borders  outwards.  This  latter  movement 
is  resisted  by  the  overlapping  of  the  great  wing  of  the  sphenoid 
and  squamous  bone.  From  the  latter  it  is  transmitted  by 
the  zygoma  to  the  superior  maxilla  and  frontal  bone,  and 
patients  frequently  complain  of  pain  in  the  face  after  receiving 
such  injuries.  The  occiput  is  not  similarly  provided  with 
means  of  dissipating  the  force  of  blows  applied  to  it,  and  is 
generally  more  readily  fractured. 

The  base  of  the  skull,  developed  from  cartilage,  is  of  much 
more  varying  thickness  than  the  vault.  The  bones  do  not 
interdigitate  as  those  of  the  vault  do,  and  they  are  pierced 
by  numerous  foramina. 

The  ANTERIOR  FOSSA  lies  at  a  considerably  higher  level 
than  the  other  fossae.  The  bone  constituting  its  base  is  ex- 
tremely thin,  and,  forming  as  it  does  the  roof  of  the  orbital 
and  nasal  cavities,  is  easily  fractured  by  instruments  thrust 
into  them.  Such  fractures  are  dangerous— not  so  much  from 
probable  damage  to  the  anterior  lobes  of  the  brain,  as  from 
the  great  liability  to  entrance  of  organisms  to  the  meninges 
and  brain.  Sometimes  in  nasal  injuries  affecting  the  ethmoid 
the  anterior  end  of  the  longitudinal  sinus  may  be  torn,  torrents 
of  blood  escaping  with  a  hissing  noise  through  the  dilated 
nostrils.  Where  the  nasal  mucous  membrane  is  torn  in 
fracture  of  the  anterior  fossa,  bleeding  from  the  nose  occurs, 
and  if  mucous  membrane,  bone,  and  dura  are  all  ruptured, 
cerebro-spinal  fluid  may  escape.  Where  ths  orbital  plate  of  the 
frontal  is  broken,  subconjunctival  ecchymosis  generally  appears 
a  few  days  after  the  accident,  travelling  from  behind  forwards, 
and  in  severe  cases  proptosis  may  occur.  The  anterior  fossa 
lodges  the  frontal  lobes  of  the  cerebrum. 

The.  MIDDLE  FOSSA  is  situated  at  a  considerably  lower  level 
than  the  anterior,  and,  viewed  from  above,  is  like  a  triangular 
box,  the  base  of  which,  directed  toward  the  surface,  is  covered 
by  the  squamous  of  the  temporal  and  a  small  portion  of  the 
sphenoid,  while  the  apex  is  formed  by  the  sella  turcica,  the 
anterior  wall  by  the  great  wing  of  the  sphenoid,  and  the  pos- 
terior wall  by  the  petrous  of  the  temporal. 

The  middle  fossa  contains  the  temporo-sphenoidal  lobe  of 
the  brain,  and  its  enclosing  form  is  of  importance  as  thereby 
the  pressure  caused  by  temporo-sphenoidal  abscess  is  directed 


THE  HEAD  13 

upwards'to  the  motor  cortex,  and  especially  the  face  centre. 
Lodged  at  the  apex  of  the  triangle,  in  a  depression  on  the 
anterior  surface  of  the  petrous  and  enclosed  in  a  fold  of  dura 
mater,  lies  the  GASSERIAN  GANGLION. 

Almost  immediately  under  the  ganglion  lies  the  internal 
carotid  artery,  passing  down  to  the  foramen  lacerum  medium, 
while  under  it  again  lies  the  cartilaginous  extremity  of  the 
Eustachian  tube.  This  relationship  may  be  a  cause  of  the 
inflammatory  conditions  sometimes  found  affecting  the  dural 
sheath  of  the  Gasserian  ganglion,  and  giving  rise  to  a  terrible 
form  of  trigeminal  neuralgia,  which  can  only  be  relieved  by 
removal  of  the  ganglion.  The  ganglion  sends  off  the  three 
branches  of  the  fifth  nerve  ;  the  first,  or  ophthalmic,  passing 
along  with  the  third,  fourth,  and  sixth  nerves,  and  the  ophthal- 
mic vein  through  the  sphenoidal  fissure  ;  the  second,  or  superior 
maxillary,  through  the  foramen  rotundum  ;  and  the  third,  or 
inferior  maxillary,  along  with  the  small  meningeal  artery, 
through  the  foramen  ,ovale.  The  ganglion  is  most  easily 
and  safely  reached  by  making  an  osteoplastic  flap  of  cheek 
and  anterior  wall  of  antrum  of  Highmore,  following  the  inferior 
orbital  nerve  back  through  the  spheno-maxillary  fossa  to 
the  foramen  rotundum,  laying  the  foramen  rotundum  and 
the  foramen  ovale  into  one  by  means  of  a  bur,  and  then 
incising  the  bulging  dural  pouch  in  which  the  ganglion  lies, 
and  twisting  out  the  ganglion  by  means  of  the  two  great 
trunks.  Thus  the  subdural  space  is  not  opened  into,  nor  the 
brain  exposed  (Macewen).  In  the  posterior  or  petrous  wall 
of  the  middle  fossa  lie  the  middle  ear,  mastoid  antrum,  etc., 
and,  as  the  wall  of  bone  separating  these  structures  from  the 
middle  fossa  is  very  thin,  disease  spreads  readily  from  them 
to  the  meninges  and  the  tern poro- sphenoidal  lobe. 

Entering  the  fossa  at  the  foramen  spinosum,  a  little  external 
to  the  foramen  ovale  is  the  MIDDLE  MENINGEAL  artery,  which 
runs  first  outwards  and  then,  divided  into  anterior  and 
posterior  branches,  upwards  over  the  external  wall  of  the 
fossa,  which  is  grooved,  and  sometimes  tunnelled,  to  receive 
it.  Owing  to  its  intimate  relations  with  the  bone,  this  artery 
is  not  infrequently  torn  in  cases  of  fracture  of  these  parts, 
causing  extensive  extradural  haemorrhage,  and  compression 
of  the  brain. 

The  crests  of  the  ridges  forming  the  triangular  fossa  are 


14  SURGICAL  ANATOMY 

occupied  by  sinuses.  These  intracranial  sinuses  are  formed 
by  a  splitting  of  the  dura  mater,  and  have  a  triangular 
section,  with  rounded  base.  Anteriorly,  running  along 
the  sphenoidal  crest  is  the  small  and  unimportant  spheno- 
parietal  sinus  ;  internally  the  apex  is  occupied  by  the  large 
and  very  important  cavernous  sinus  which,  with  the  internal 
carotid  artery,  lies  in  a  groove  on  the  body  of  the  sphenoid. 
The  two  cavernous  sinuses  are  intimately  connected  by  means 
of  the  circular  sinus.  Posteriorly,  connecting  the  cavernous 
with  the  knee  of  the  lateral  sinus  is  the  superior  petrosal  sinus. 
running  along  the  petrous  crest.  It  is  not  a  large  sinus,  and 
is  not  so  important  as  the  inferior  petrosal. 

The  POSTERIOR  FOSSA,  viewed  bilaterally,  is  roughly  trian- 
gular in  shape,  with  a  rounded  base.  It  is  covered  in  by  the 
arched  tentorium,  save  at  the  apex,  where  there  is  an  oval  open- 
ing in  the  tentorium  for  the  passage  of  the  mesencephalon. 
The  occipital  lobes  rest  upon  the  upper  surface  of  the  tentorium, 
while  within  the  fossa  the  cerebellum,  medulla,  and  portions 
of  all  the  cranial  nerves,  except  the  first  three,  are  contained. 
The  posterior  fossa  may  thus  be  compared  to  a  shut  box, 
the  tentorium  forming  the  lid,  and  it  can  be  readily  under- 
stood why  pressure,  as  from  abscess,  occurring  in  this  fossa 
has  a  rapid  and  general  effect  upon  the  cerebellum. 

The  cerebellum  is  not,  as  is  generally  stated,  entirely  con- 
fined to  the  posterior  fossa.  On  the  contrary,  its  lower  ex- 
tremity enfolding  the  medulla  frequently  passes  down  through 
the  foramen  magnum,  to  terminate  opposite  the  atlas,  or  even 
the  axis  (see  plate).  The  tentorium  splits  at  its  bony  inser- 
tions to  form  posteriorly  the  large  lateral  sinuses,  and  anteriorly 
the  superior  petrosal  sinuses.  Emerging  antero-laterally 
from  the  posterior  surface  of  the  petrous  are  the  seventh  and 
eighth  nerves,  and  it  is  by  the  sheaths  of  these  nerves  that 
pyogenic  mischief  is  frequently  carried  from  the  middle  and 
internal  ear  to  the  meninges,  causing  generalized  meningitis. 
Running  from  the  posterior  end  of  the  cavernous  sinus  down 
to  the  jugular  bulb  is  the  inferior  petrosal  sinus. 

While  FRACTURE  OF  THE  BASE  of  the  skull  may  be  due  to 
either  direct  or  -indirect  violence,  it  most  frequently  occurs 
by  extension  from  the  vault.  The  fracture  may  involve  the 
anterior,  middle,  or  posterior  fossa,  and  the  symptoms  differ 
according  to  the  fossa  involved. 


THE  HEAD 


In  FRACTURE  OF  THE  ANTERIOR  FOSSA  there  is  generally 
bleeding  from  the  nose,  as  already  described  ;  proptosis  of  the 
eyeball  from  accumulation  of  blood  behind  it,  with  the 
subjective  sensation  of  flashes  of  light  from  irritation  of  the 
optic  nerve  ;  effusion  of  blood  into  the  conjunctiva,  and  later 


FIG.  3.  — CORONAL  HEAD  SECTION  PASSING  THROUGH  PORTION 
OF  THE  SPINAL  CANAL. 

Note  opposite  i  the  superior  longitudinal  sinus  and  the  falx  cerebri  extending  vertically 
downwards  from  it.  At  2,  the  corpus  callosum,  and  beyond  it  the  lateral  ventricle  (dilated) 
with  the  optic  thalamus  projecting  into  its  outer  side.  Opposite  3,  the  third  ventricle,  and 
beyond  it  the  internal  capsule  (white),  lenticular  nucleus,  external  capsule  (white),  clau- 
strum,  and  then  the  surface  of  the  island  of  Reil  enveloped  by  the  parietal  and  temporo- 
sphenoidal  lobes.  Opposite  4,  the  pons  and  portion  of  the  middle  cerebellar  peduncle,  and 
below  it  the  medulla,  cord,  and  upper  spinal  nerves.  Beyond  the  pons,  the  cerebellum  roofed 
in  by  tentorium.  Note  how  the  cerebellum  projects  down  through  the  foramen  magnum, 
enveloping  the  medulla. 

into  the  eyelids,  coming  on  some  time  after  the  injury.  The 
speech  centre  may  be  affected  in  left-sided  lesions,  and  occa- 
sionally the  face  centre  is  involved. 

In  FRACTURE  OF  THE  MIDDLE  FOSSA  there  is  generally 
bleeding  from  the  ear,  the  membrana  having  been  ruptured ; 


1 6  SURGICAL  ANATOMY 

but  occasionally  the  blood  may  pass  down  the  Eustachian 
tube  and  be  swallowed,  and,  if  subsequently  vomited,  may 
lead  one  to  suspect  internal  injuries.  Where  the  dura  is 
ruptured,  escape  of  cerebro  -  spinal  fluid  by  the  ear  is  fre- 
quently met  with,  the  fluid  in  some  cases  finding  its  way  into 
the  middle  ear  through  a  fracture  of  the  tympanic  attic,  and 
in  others  coming  along  the  sheaths  of  the  seventh  and  eighth 
nerves  where  the  internal  ear  is  involved.  While  a  hernia 
cerebri  might  possibly  protrude  through  the  ear,  it  certainly 
is  of  very  rare  occurrence.  Facial  paralysis  from  involvement 
of  the  facial  nerve  is  common,  and  deafness  from  involvement 
of  the  eighth  nerve  is  less  so.  Pharyngeal  ecchymosis  fre- 
quently appears  within  a  few  days  of  the  accident. 

In  FRACTURE  OF  THE  POSTERIOR  FOSSA  the  movements  of 
the  tongue  and  of  swallowing  are  generally  impaired,  owing  to 
involvement  of  the  ninth  nerve  about  the  jugular  foramen, 
or  the  twelfth  about  the  anterior  condyloid  foramen,  while 
ecchymosis  over  the  mastoid  and  posterior  triangle  of  the 
neck  appears  some  days  after  the  injury,  the  same  region  being 
tender  to  pressure. 

The  Cerebral  Membranes. — The  brain  is  generally  described 
as  having  three  coverings — the  dura,  arachnoid,  and  pia  mater. 
Surgically  speaking,  the  pia  and  arachnoid  are  one  over  the 
greater  part  of  their  extent,  and  may  be  treated  together. 

The  DURA  MATER  lines  the  entire  cavity  of  the  cranium, 
and  is  continuous  with  the  dura  of  the  spine  through  the 
foramen  magnum.  It  sends  prolongations  along  the  nerves — 
e.g.,  the  optic,  to  fuse  with  the  sclerotic  ;  the  seventh  and 
eighth  nerves,  to  the  internal  ear.  It  is  a  tough  fibrous  mem- 
brane, which  acts  both  as  internal  periosteum  of  the  skull 
and  as  a  covering  for  the  brain.  It  is  said  to  be  the  chief 
source  of  blood-supply  to  the  skull,  but  in  operations  on  the 
brain  large  osteoplastic  flaps  may  be  raised  from  the  dura 
without  untoward  effect.  Like  all  periostea,  of  course,  the 
dura  mater  has  no  bone-forming  function,  the  function  of  a  peri- 
osteum being  to  supply  blood  to  the  bone,  and  to  act  as  a 
limiting  membrane  to  the  osteoblasts. 

In  cases  where  the  skull  has  been  damaged,  the  dura,  from 
its  tough,  unyielding  character,  forms,  along  with  the  scalp, 
an  excellent  protection  for  the  underlying  brain.  The  dura 
is  rather  loosely  adherent  over  the  vault,  a  fact  well  seen  in 


THE  HEAD  17 

raising  os^eoplastic  flaps  from  it,  but  is  more  firmly  attached 
over  the  base,  and  particularly  over  the  petrous,  sella  turcica, 
and  cribriform  plate,  fractures  of  these  parts  being  generally 
associated  with  tearing  of  the  dura.  It  is  more  adherent  to 
the  vault  during  infancy  and  old  age,  and  frequently  becomes 
firmly  attached  in  pathological  conditions.  By  means  of  its 
processes,  the  falx  cerebri  and  tentorium  cerebelli,  it  supports 
the  brain,  and  limits  the  transmission  of  impulses  received 
by  injury  from  one  part  to  another.  It  forms  the  great  blood 
sinuses  of  the  skull  by  splitting.  The  dura  does  not  possess 
a  true  lymphatic  system,  and  while  it  contains  numerous 
lymphatic  spaces,  it  does  not  readily  yield  a  passage  to 
purulent  processes.  EXTRADURAL  ABSCESS,  even  when  large, 
and  causing  considerable  tension,  frequently  remains  external 
to  the  dura,  and  does  not  give  rise  to  leptomeningitis.  Extra- 
dural  abscess  is  sometimes  caused  by  extension  through  the 
bone  of  septic  mischief  from  scalp  wounds.  The  pus  may  not 
involve  either  pia  or  brain,  but  partial  destruction  of  the  over- 
lying bone  may  occur,  toxins  escape,  and  oedema  of  the  over- 
lying soft  parts  be  caused,  probably  some  considerable  time 
after  the  primary  wound  has  healed.  This  condition  is  known 
as  '  Pott's  puffy  tumour.' 

While  EXTRADURAL  HEMORRHAGE  is  generally  localized,  it 
is  often  caused  by  rupture,  from  fracture,  of  the  middle 
meningeal  artery,  and  may  then  be  of  sufficient  extent  to  cause 
death.  The  vessel  lies  in  a  groove,  or  even  a  tunnel,  in  the 
bone,  and  the  anterior  branch  is  the  one  most  often  affected. 
The  effused  blood  separates  the  dura  from  the  cranium,  and 
causes  pressure  on  the  brain,  while  the  vessel  remains  within 
its  osseous  canal.  The  artery  has  been  torn  by  blows  without 
fracture  of  the  skull.  In  all  such  cases  it  is  important  to  re- 
member that  unconsciousness  often  comes  on  gradually,  the 
patient  being  able  to  speak  intelligently  and  walk  about  for 
perhaps  an  hour  or  so  after  the  accident.  The  dura  is  separated 
from  the  pia  arachnoid  by  a  slight  space — the  subdural  space 
— which  contains  cerebro-spinal  fluid. 

The  pia  arachnoid  may  be  considered  surgically  as  a  single 
flocculent  membrane.  The  arachnoid  portion  does  not  dip 
down  into  the  sulci  and  is  smooth  on  its  dural  aspect,  while 
it  is  intimately  connected  with  the  pia  underneath  by  a  fine 
filamentous  structure  whose  interstices  are  filled  with  cerebro- 


i8  SURGICAL  ANATOMY 

spinal  fluid,  forming  the  SUBARACHNOID  SPACE.  In  most 
places  this  space  is  insignificant,  but  particularly  at  the  base 
of  the  brain  it  expands  greatly,  forming  the  WATER-BED  of 
the  brain.  This  bed  is  of  great  importance  surgically,  as  it 
prevents  the  brain,  in  severe  injuries,  from  being  impacted 
against  the  base  of  the  skull.  It  extends  forwards  as  far  as 
the  optic  nerves,  the  largest  spaces  being  the  cisterna  pontis, 
under  the  pons  and  medulla,  and  cisterna  magna,  between  the 
roof  of  the  fourth  ventricle  and  under  surface  of  the  cere- 
bellum. The  frontal  lobes,  resting  on  the  anterior  fossa,  do 
not  possess  this  support,  and  thus  are  not  infrequently 
lacerated  by  injury. 

The  PIA  MATER  is  a  delicate  membrane  which  supports  a 
rich  vascular  network  for  the  supply  of  the  brain,  the  whole 
being  floated  by  the  cerebro-spinal  fluid.  The  pia  may  thus 
be  regarded  as  the  blood-supplying  covering  of  the  brain, 
just  as  the  dura  supplies  the  skull.  The  pia  not  only  dips 
down  into  the  sulci,  and  turns  in  at  the  transverse  fissure  to 
form  the  velum  interpositum  and  choroid  plexuses,  but  also 
sends  prolongations  along  the  cerebral  vessels  into  the  brain 
(perivascular  sheaths),  so  that  it  is  easy  to  understand  how 
a  degree  of  encephalitis  must  almost  certainly  accompany 
leptomeningitis. 

The  pia,  like  the  dura,  is  continuous  with  that  of  the  cord, 
and  similarly  sends  prolongations  along  the  cranial  and  spinal 
nerves. 

The  continuity  of  cerebro-spinal  fluid  between  the  outside 
and  inside  of  the  brain  and  the  cord  is  of  importance.  When 
the  brain  expands,  as  it  does  at  each  cardiac  impulse,  fluid 
is  forced  from  the  cranial  cavity  to  the  spinal  portion,  and 
returns  on  diastole,  the  pressure  being  thus  kept  constant. 
In  congested  conditions  of  the  ganglia  also  fluid  would  be 
displaced  through  the  foramen  of  Magendie  and  other  com- 
munications, and  equilibrium  thus  restored. 

SUBDURAL  H/EMORRHAGE,  unlike  the  extradural  variety,  is 
often  very  extensive,  extending  both  above  and  below  the 
arachnoid,  and  sometimes  even  to  the  cord.  It  may  arise 
from  rupture  of  the  vessels  of  the  pia  arachnoid,  or,  if  the 
dura  be  torn,  may  extend  from  either  the  middle  meningeal 
artery  or  from  one  of  the  sinuses,  such  as  the  superior  longi- 
tudinal, cavernous  or,  lateral.  Even  after  blood  has  clotted 


THE  HEAD  19 

in  the  subdural  space,  it  may  slip  from  its  position,  which 
perhaps  was  over  the  vertex,  and  cause  death  by  pressure  on 
the  medulla. 

MENINGITIS,  or  inflammation  of  the  cerebral  membranes, 
may  affect  the  dura  mater  (pachymeningitis)  or  the  pia 
arachnoid  (leptomeningitis).  Pachymeningitis  is  generally 
due  to  pyogenic  organisms,  and,  if  not  accompanied  by  lepto- 
meningitis, is  generally  localized.  Leptomeningitis,  when  due 
to  pyogenic  organisms,  is  generally  diffuse,  often  extending 
along  the  membranes  of  the  cord,  and  accompanied  by  a  degree 
.of  encephalitis.  Pyogenic  infection  of  the  cerebral  membranes 
may  arise  from  many  causes,  notably  middle-ear  disease. 
Tubercle  is  generally  conveyed  by  the  blood-stream,  and 
involves  the  pia  mater,  particularly  at  the  base  of  the  brain 
and  along  the  Sylvian  fissure. 

A  congenital  protrusion  of  the  membranes,  or  meningocele, 
occurs  most  frequently  posteriorly,  through  the  occiput,  and 
less  frequently  at  the  root  of  the  nose.  When  accompanied 
by  brain  matter  it  is  called  a  meningo-encephalocele  or  en- 
cephalocele,  and  when  the  protruded  portion  is  distended  by 
ventricular  fluid  it  is  called  hydrencephalocele. 

THE  BRAIN. 

Of  importance  to  the  surgeon  is  a  knowledge  of  the  loca- 
tion of  the  principal  brain  centres  and  their  relation  to  the 
surface  of  the  head.  If  two  parallel  lines  be  drawn  from  the 
nasion  in  front  to  a  position  J  inch  above  the  superior  curved 
line  of  the  occiput  behind,  one  J  inch  to  the  right  and  the  other 
J  inch  to  the  left  of  the  middle  line,  they  will  represent  the 
inner  margins  of  the  right  and  left  cerebral  hemispheres, 
while  the  space  between  them  is  occupied  by  the  superior 
longitudinal  sinus,  which  enlarges  as  it  passes  back  and  lies 
rather  to  the  right  of  the  middle  line,  owing  to  the  greater  size 
of  the  left  hemisphere.  A  line  drawn  from  the  nasion  in  front 
to  the  external  angular  process  of  the  frontal  with  an  upward 
convexity  fully  J  inch  above  the  orbital  margin,  thence  carried 
backwards  along  the  upper  border  of  the  zygoma  to  the  pre- 
auricular  point,  and  from  that  to  the  external  occipital  pro- 
tuberance, will  roughly  indicate  the  inferior  margin  of  the 
cerebrum.  A  line  drawn  from  the  nasion  to  the  inion  (naso- 

2 — 2 


20  SURGICAL  ANATOMY 

iniac  line),  and  divided  into  four  equal  parts,  will  represent  the 
position  of  the  PARIETO-OCCIPITAL  SUTURE  at  the  junction  of 
its  third  and  fourth  quarters.  The  POSTERIOR  HORIZONTAL 
LIMB  OF  THE  SYLVIAN  FISSURE  will  be  represented  by  the 
anterior  half  of  a  line  drawn  from  the  pterion  to  the  parieto- 
occipital  suture,  while  the  SHORT  ANTERIOR  HORIZONTAL 
(\  inch  long)  and  VERTICAL  (f  inch  long)  processes  of  the 
Sylvian  fissure  run  from  the  pterion  in  the  directions  in- 
dicated by  their  names.  The  position  of  the  FISSURE  OF 
ROLANDO  is  indicated  by  a  line  commencing  J  inch  behind 
the  mid-point  of  the  naso-iniac  line,  and  running  down  and 
forwards  at  an  angle  of  67^  degrees  (three-quarters  of  a  right 
angle)  to  meet  the  Sylvian  line. 

The  frontal  portion  of  the  cerebrum  is  bounded  centrally 
and  inferiorly  by  the  lines  already  given,  while  posteriorly 
it  is  bounded  by  the  Rolandic  fissure. 

It  consists  of  superior,  middle,  and  inferior  convolutions, 
and  also  of  a  precentral  convolution,  which  is  about  f  inch 
broad,  and  is  bounded  in  front  by  the  precentral  sulci,  which 
run  parallel  to  the  Rolandic  fissure.  The  third  or  inferior 
left  frontal  convolution — Broca's  lobe — contains  the  MOTOR 
SPEECH  AREA,  and  would  be  indicated  on  the  surface  by  a 
point  nearly  an  inch  in  front  of  the  Rolandic  area,  and  slightly 
below  the  temporal  ridge.  It  lies  between  the  anterior  and 
the  ascending  limbs  of  the  Sylvian  fissure.  The  PRECENTRAL 
CONVOLUTION  is  the  most  important  motor  area  of  the  brain, 
and,  according  to  Sherrington,  contains  all  the  centres  pre- 
viously attributed  to  the  posterior  central  convolution.  This 
motor  area  occupies  practically  the  whole  length  and  breadth 
of  the  precentral  convolution,  and  extends  into  the  depth  of 
the  Rolandic  fissure.  Whether  the  posterior  central  con- 
volution (belonging  to  the  parietal  region)  is  also  involved  is 
at  present  uncertain.  The  area  for  the  lower  limb  occupies 
the  region  of  the  upper  third  of  the  Rolandic  fissure,  and 
also  dips  superiorly  into  the  longitudinal  fissure.  The  area 
for  the  upper  limb  occupies  the  region  of  the  middle  third  of 
the  Rolandic  fissure,  while  the  area  for  the  face  occupies  the 
lower  third. 

The  fissure  of  Sylvius  separates  the  lower  end  of  the  Ro- 
landic area  from  the  temporal  lobe,  and  as  the  latter  is  fre- 
quently affected  by  cerebral  abscess,  the  pressure  from  which 


THE  HEAD  21 

is  directeoVchiefly  upwards,  it  follows  that  the  face  centre  is 
frequently  affected  in  such  cases  (causing  an  incomplete 
paralysis  of  the  face  on  the  opposite  side),  whereas  the  arm  is 
rarely,  and  the  leg  is  practically  never,  affected.  Further, 
it  should  be  noted  that  the  face  is  first  affected,  and  the  leg, 
if  affected  at  all,  last,  the  affection  coming  on  gradually 
(compare  with  internal  capsule). 

The  parietal  lobe  extends  from  the  longitudinal  fissure 
above  to  the  Sylvian  fissure  below,  and  is  bounded  in  front 
by  the  Rolandic  fissure  and  behind  by  a  line  drawn  from  the 
position  of  the  parieto-occipital  fissure  to  the  asteric  point 
(parieto-mastoid  line).  It  presents  the  posterior  central  con- 
volution, bounded  posteriorly  by  the  posterior  central  sulci, 
which  are  parallel  to  and  f  inch  behind  the  Rolandic  fissure. 
It  also  presents  a  superior  parietal  lobule  and  superior  marginal 
and  angular  convolutions.  The  latter  is  supposed  to  contain 
the  word-seeing  centre,  and  lies  just  behind  and  above  the 
posterior  extremity  of  the  Sylvian  line. 

The  temporal  lobe  is  limited  above  by  the  Sylvian  fissure, 
below  by  the  line  indicating  the  lower  level  of  the  brain.  It 
extends  anteriorly  to  about  f  inch  from  the  outer  margin  of 
the  orbit,  while  posteriorly  it  is  bounded  by  the  lower  portion 
of  the  parieto-mastoid  line.  It  presents  superior,  middle, 
and  inferior  convolutions,  the  two  former  separated  by  the 
parallel  fissure,  and  the  latter  lying  over  the  thin  tegmina  of 
the  middle  ear  and  mastoid,  and  being  frequently  infected 
by  pyogenic  invasion  through  these  thin  plates  of  bone.  As 
the  temporal  lobe  is  limited  anteriorly,  posteriorly,  and 
externally  by  bone,  the  pressure  of  an  abscess  must  be 
directed  upwards  and  inwards.  The  upward  pressure  affects 
the  motor  area  of  the  face,  while  the  inward  pressure  affects 
the  third  nerve,  causing  first  irritation  (contraction  of  pupil 
on  same  side),  and  later  paralysis  (dilatation  of  pupil  on  same 
side)  of  the  nerve.  The  central  portion  of  the  superior 
temporal  convolution  is  supposed  to  contain  the  word-hearing 
centre. 

The  occipital  lobe  lies  posterior  to  the  parieto-occipital 
fissure,  but  is  not  sharply  demarcated  from  the  parietal  and 
temporal  lobes,  which  merge  with  it.  It  presents  superior, 
middle,  and  inferior  convolutions.  The  line  from  the  pre- 
auricular  point  to  the  external  occipital  protuberance  indi- 


22  SURGICAL  ANATOMY 

cates  posteriorly  the  position  of  separation  between  cerebrum 
and  cerebellum  by  the  tentorium,  and  of  the  lateral  sinus, 
which  is  formed  by  a  splitting  of  the  dural  processes  which 
form  the  tentorium. 

The  cerebellum  occupies  a  strictly  limited  space  between 
the  tentorium  and  the  containing  bone,  and  hence,  when 
affected  by  abscess,  and  even  by  tumour,  is  unable  to  accom- 
modate the  increased  mass,  the  pain  in  such  conditions  being 
generally  very  intense,  owing  to  pressure.  Further,  as  there 
is  no  septum  between  the  two  halves  of  the  cerebellum,  it  is 
generally  difficult  to  determine  the  side  occupied  by  a  lesion 
by  the  symptoms  alone,  the  pressure  being  diffused  over  both 
sides.  Where  the  cerebellum  is  affected  by  abscess,  this  most 
often  has  arisen  from  the  mastoid  region,  and  the  treatment 
necessitates  a  thorough  opening  up  of  the  mastoid,  exposing, 
and,  if  necessary,  ablating  the  sigmoid  sinus  to  prevent 
dissemination  of  the  septic  matter  within  it,  and  then,  by 
cutting  the  bone  still  further  backwards,  exposing  and  opening 
the  cerebellar  fossa  and  evacuating  the  abscess.  Tumour 
of  the  cerebellum  may  be  reached  by  an  incision  under  the 
external  occipital  protuberance,  shelling  the  muscles  (the  parts 
generally  bleeding  freely),  and  then  either  trephining  or 
cutting  a  bone  flap,  and  finally  opening  the  cerebellar  dura. 

The  island  of  Reil  lies  at  the  bottom  of  the  posterior 
horizontal  limb  of  the  Sylvian  fissure,  and  is  thus  closely 
related  to  the  frontal,  parietal,  and  temporal  lobes  by  which 
it  is  enveloped.  A  short  distance  under  its  surface,  and 
conforming  to  it,  is  a  thin  plane  of  grey  matter,  the  claustrum  ; 
then  follows  a  thin  plane  of  white  matter,  called  the  external 
capsule  ;  and  then  comes  the  lenticular  nucleus.  The  lenticular 
nucleus  corresponds  in  extent  with  the  island  of  Reil,  and 
lies  nearly  J  inch  from  its  surface.  Its  internal  surface  is 
more  convex  than  its  external  (the  convexity  being  directed 
inwards),  and  forms  the  outer  boundary  of  the  internal  capsule. 
The  INTERNAL  CAPSULE  in  horizontal  sections  is  bent  at  the 
junction  of  its  anterior  and  middle  thirds,  the  bend  or  genu 
conforming  to  the  most  prominent  part  of  the  lenticular 
nucleus,  while  on  the  inner  side  the  anterior  limb  is  bounded 
by  the  caudate  nucleus  and  the  posterior  limb  by  the  optic 
thalamus.  Surgically  the  anterior  half  of  the  posterior  limb 
(middle  third  of  whole  and  not  i  inch  long  in  horizontal 


THE  HEAD  23 

section),  *which  lies  about  i  inch  from  the  surface  of  the 
island  of  Reil,  is  of  most  importance,  as  it  contains  the  fibres 
descending  from  the  motor  area  of  the  cortex.  Lying  close 
to  the  genu  are  the  fibres  going  to  the  facial  nucleus,  then 
come  some  going  to  the  hypoglossal  nucleus,  and  further  back 
are  the  fibres  going  to  the  pyramidal  tracts,  which  influence 
the  motor  cells  in  the  anterior  cornua  of  the  cord  for  the 
supply  of  the  limbs.  Those  fibres  which  supply  the  arm  lie 
in  front  of  those  supplying  the  leg.  The  remainder  of  the 
capsule  is  occupied  by  sensory  and  communicating  fibres. 
(According  to  Dr.  Foster,  fibres  for  the  eye  and  head  lie  even 
anterior  to  the  genu.) 

Owing  to  the  crowding  of  the  fibres  in  the  internal  capsule, 
a  lesion  about  the  genu,  even  a  small  haemorrhage,  produces 
an  extensive  result,  hemiplegia  or  paralysis  of  the  whole  of  the 
opposite  side  resulting,  while  a  sensory  disturbance  generally 
accompanies  it.  The  internal  capsule  is  very  rarely  affected 
by  pressure  from  temporo-sphenoidal  abscess,  but  when  it  is, 
the  paralysis  generally  affects  first  the  leg  and  then,  in  rapid 
succession,  the  arm  and  face  (compare  with  affection  of  motor 
cortex.) 

The  basal  ganglia  consist  of  (a)  CORPORA  STRIATA,  com- 
posed of  the  caudate  and  lenticular  nuclei,  of  which  the 
former  projects  into  the  lateral  ventricle,  while  the  latter  is 
extraventricular,  lying  to  the  outer  side  of  the  caudate 
nucleus  and  of  the  optic  thalamus ;  (b)  OPTIC  THALAMI,  the 
upper  surfaces  of  which  assist  in  the  formation  of  the  floor 
of  the  lateral  ventricles,  while  parts  are  covered  by  the  velum 
interpositum  of  the  pia  mater  ;  (c)  CLAUSTRA  lying  outside 
the  lenticular  nuclei ;  (d)  CORPORA  QUADRIGEMINA,  CORPORA 
GENICULATA  (internal),  and  PINEAL  BODY,  which  are  situated 
below  the  posterior  extremity  of  the  optic  thalami,  and  rather 
internal  to  them,  forming  practically  the  posterior  boundary 
of  the  third  ventricle  and  the  roof  of  the  commencement 
of  the  aqueduct  of  Sylvius,  which  connects  the  third  and  fourth 
ventricles  ;  (e)  AMYGDALOID  NUCLEI,  which  lie  in  the  temporal 
lobes,  in  front  and  above  the  extremity  of  the  descending 
horns  of  the  lateral  ventricles.  Not  only  do  these  ganglia 
generally  appear  to  be  connected  with  the  reception  and 
transmission  of  impulses  from  and  to  the  brain,  but  they  also 
seem  to  exercise  a  semi-independent  control  of  the  more  com- 


24  SURGICAL  ANATOMY 

plex  reflexes  and  co-ordination  of  movement.  The  function 
of  the  corpora  striata  cannot  be  further  denned.  They  are 
intimately  associated  with  the  optic  thalami  and  with  the 
cerebral  cortex.  The  optic  thalamus,  especially  its  hinder 
portion,  together  with  the  external  geniculate  body  situated 
at  its  posterior  extremity,  and  the  superior  corpus  of  the 
quadrigemina,  is  intimately  associated  with  sight.  In  addition, 
many  afferent  fibres  pass  through  the  thalamus  from  the 
tegmentum  of  the  crus  to  the  cortex,  while  others,  also  going 
to  the  cortex  through  the  internal  capsule,  originate  in  the 
thalamus  (thalamic  radiation).  The  inferior  corpora  of  the 
quadrigemina  and  also  the  internal  corpora  geniculata  are 
connected  with  hearing. 

The  functions  of  the  other  nuclei  are  indefinite  or  unknown. 

The  body  of  the  lateral  ventricle  is  situated  internal  to  the 
caudate  nucleus,  which  forms  part  of  its  outer  boundary  and 
floor.  The  corpus  callosum  forms  its  roof,  while  it  is  separated 
from  its  neighbour  of  the  opposite  side  by  the  posterior  part 
of  the  septum  lucidum  and  junction  of  corpus  callosum  with 
the  fornix.  From  the  body  of  the  ventricle  an  anterior  horn 
projects  a  short  distance  forwards  and  outwards,  while  pos- 
teriorly, at  the  splenium  or  posterior  curled  end  of  the 
corpus  callosum,  the  posterior  and  descending  horns  diverge. 
The  position  of  the  divergence  is  represented  on  the  surface  by 
a  point  J  inch  vertically  above  the  external  auditory  meatus. 
The  descending  horn  curves  round  the  posterior  extremity 
of  the  optic  thalamus,  and  projects  forwards  and  inwards 
along  the  temporal  lobe  toward  the  temporal  pole.  The 
posterior  horn  curves  backwards  and  inwards  into  the  occipital 
lobe.  The  bodies  of  the  two  lateral  ventricles  communicate 
anteriorly  with  the  third  ventricle,  which  lies  beneath  them, 
by  the  foramina  of  Monro,  and  hence  with  one  another.  The 
THIRD  VENTRICLE  communicates  with  the  FOURTH  VENTRICLE 
by  the  aqueduct  of  Sylvius,  whence  it  becomes  continuous 
with  the  central  canal  of  the  cord. 

The  lateral  ventricles  communicate  directly  with  the  sub- 
arachnoid  space  by  means  of  the  slit-like  openings  at  the 
extremity  of  each  descending  horn,  and  indirectly  by  the 
foramen  of  Magendie  and  lateral  recesses  of  the  fourth 
ventricle. 

The  subarachnoid  space  is  best  developed  on  the  under 


THE  HEAD  25 

surface  cxf  the  medulla  and  the  cerebellum,  forming  the  water- 
bed,  or  cisterna  magna  ;  but  the  various  spaces  freely  communi- 
cate with  one  another,  with  the  spinal  subarachnoid,  and,  by 
means  of  the  Pacchionian  bodies,  with  the  longitudinal  and 
other  sinuses.  Thus  the  ventricular  system  normally  com- 
municates freely  with  the  subarachnoid  system,  and  an  equality 
of  pressure  is  preserved.  In  HYDROCEPHALUS  the  ventricles 
of  the  brain  become  distended,  sometimes  to  such  an  extent 
as  to  leave  only  a  narrow  rim  of  brain  matter  between  them 
and  the  dura.  The  condition  is  supposed  to  be  due  to  blocking 
of  the  foramina  of  Magendie  and  the  other  communications 
mentioned. 

TAPPING  OF  THE  VENTRICLES  of  the  brain  has  been  occa- 
sionally advocated  in  the  treatment  of  hydrocephalus.  Two 
horizontal  lines,  one  2  inches  above  and  the  other  J  inch 
above,  and  both  parallel  to,  the  zygoma  represent  roughly 
the  upper  and  lower  limits  of  the  cornua  of  the  ventricles, 
while  two  vertical  lines,  the  anterior  through  the  junction  of 
the  anterior  and  middle  third  of  the  zygoma,  and  the  other 
2  inches  behind  the  tip  of  the  mastoid  process,  define  the 
anterior  and  posterior  limits.  A  permanent  communication 
may  be  established  between  the  ventricle  and  either  the 
subarachnoid  space  or  the  subcutaneous  tissues,  and  the 
distension  thereby  relieved. 

In  health  the  brain  pulsates  markedly  when  the  dura  is 
opened,  and  it  is  supposed  that  the  subarachnoid  system 
equalizes  and  distributes  the  pressure  so  caused.  Not  merely 
the  cardiac,  but  also  respiratory  effects,  can  be  traced,  the  latter 
being  due  to  the  arrest  of  the  venous  return  from  the  brain 
during  inspiration  by  the  mechanism  explained  in  connection 
with  the  sigmoid  sinus.  An  abscess  or  tumour  of  the  brain 
increases  the  intracranial  pressure,  even  a  small  abscess,  in 
its  rapid  growth,  causing  considerable  disturbance,  whereas 
a  tumour,  growing  much  more  slowly,  may  attain  consider- 
able dimensions  without  producing  marked  effects,  unless  it 
be  situated  at  a  focal  point.  On  opening  the  dura  in  such 
cases  absence  of  pulsation  is  frequently  marked  at  first,  then 
the  cerebral  matter  is  gradually  extruded  through  the  opening, 
the  pulsation  becoming  apparent  as  the  extrusion  proceeds 
with  each  cardiac  impulse.  Superficially  placed  tumours 
and  encapsulated  abscesses  may  occasionally  be  extruded 


26  SURGICAL  ANATOMY 

in  this  manner  on  opening  the  dura,  and  in  most  cases  the 
pulsation  assists  the  removal  or  evacuation  of  the  pathological 
process.  Tumours  of  the  brain  occasionally  erode  the  cranial 
cavity  and  present  externally  as  subcutaneous  pulsating 
swellings. 

Cerebral  Circulation. — The  MENINGEAL  VESSELS  are  classi- 
fied, according  to  the  fossa  they  supply,  into  anterior,  middle, 
and  posterior  meningeal  sets.  The  anterior  are  derived  from 
the  ophthalmic  artery,  the  posterior  from  the  occipital  and 
ascending  pharyngeal  of  the  external  carotid,  and  from  the 
vertebral,  while  the  middle  fossa  is  supplied  by  the  only  large 
vessel  of  the  series,  the  middle  meningeal.  The  middle 
meningeal  artery  is  derived  from  the  internal  maxillary,  and 
enters  the  skull  through  the  foramen  spinosum,  whence  it 
runs  up  and  forwards,  often  lodged  in  a  groove  or  even  a  canal 
in  the  bone,  and  divides  into  anterior  and  posterior  branches. 
Rupture  of  this  vessel,  from  fracture  of  the  skull  or  possibly 
severe  concussion,  is  the  main  source  of  extensive  extradural 
haemorrhage,  the  blood  stripping  the  dura  from  the  bone,  and 
forming  a  large  haematoma,  which  often  causes  compression, 
ending  fatally.  To  arrest  the  haemorrhage  it  is  necessary 
to  trephine  the  skull,  taking  care  not  to  cut  the  vessel  em- 
bedded in  the  bone  in  doing  so.  The  trunk  is  reached  at  a 
point  |  inch  above  the  zygoma,  the  anterior  branch  ij  inches 
behind  the  external  angular  process  of  the  frontal  and 
1 1  inches  above  the  zygoma,  and  the  posterior  branch  i -|  inches 
above  the  external  auditory  meatus.  Where  the  dura  is 
torn,  the  haemorrhage  may  become  subdural,  and  is  then 
generally  extensive,  sometimes  causing  pressure  on  the 
medulla. 

As  already  mentioned,  the  cerebral  sinuses  are  formed 
by  a  splitting  of  the  dura  mater,  and  present  a  triangular 
section,  with  rounded  base.  The  SUPERIOR  LONGITUDINAL 
SINUS  is  connected,  at  least  in  early  life,  with  the  veins 
of  the  nose,  through  the  foramen  caecum,  in  front.  As  it 
runs  backwards  it  lies  slightly  to  the  right  of  the  middle 
line,  and,  gradually  enlarging,  receives  tributaries  which 
communicate  with  the  scalp  veins.  It  ends  posteriorly 
by  joining  the  lateral  sinuses  at  the  torcular  Herophili. 
While  septic  infection  does  occasionally  extend  to  this 
sinus  through  its  communications,  causing  septic  thrombosis, 


THE  HEAD  27 

it  is  mQre  frequently  the  seat  of  marasmic  thrombosis,  such 
as  occurs  in  weakly  emaciated  children.  The  frequency 
of  the  marasmic  type  is  accounted  for  by  the  slow  circula- 
tion in  this  sinus,  due  to  (a)  tributaries  entering  at  an  angle 
opposed  to  the  direction  of  the  current ;  (b)  Pacchionian 
projections  ;  (c)  rapid  enlargement  of  the  sinus  ;  (d)  junction 
with  the  lateral  sinus  at  right  angles.  While  marasmic  throm- 
bosis occurs  more  frequently  in  azygos  sinuses,  such  as  this, 
septic  thrombosis  occurs  most  frequently  in  dual  sinuses, 
such  as  the  sigmoid.  Naevi  occurring  along  the  middle  line 
of  the  scalp  not  infrequently  communicate  with  the  sinus, 
and  hence  must  be  treated  with  caution. 

The  CAVERNOUS  SINUS  is  so  called  from  the  fibrous  strands 
which  divide  its  interior,  and  commences  by  receiving  the 
ophthalmic  vein  (whence  sepsis  may  spread  from  the  orbit), 
and  ends  by  dividing  into  the  superior  and  inferior  petrosal 
sinuses,  while  it  communicates  with  its  neighbour  through 
the  CIRCULAR  SINUS,  so  that  thrombosis  generally  extends 
from  one  side  to  the  other.  In  its  outer  wall  are  embedded 
the  internal  carotid  artery,  and  the  third,  fourth,  first  division 
of  the  fifth,  and  sixth  nerves. 

The  INFERIOR  PETROSAL  SINUS  receives  large  quantities  of 
blood  from  the  cavernous  sinus,  the  blood  being  pumped  into 
it  from  the  communicated  pulsations  of  the  internal  carotid 
artery,  which  practically  lies  in  the  cavernous  sinus.  The 
vessel  pursues  an  almost  vertical  downward  course  to  join 
the  jugular  bulb.  When  wounded,  bleeding  from  this  sinus 
is  very  difficult  to  arrest. 

The  LATERAL  SINUS  runs  first  horizontally  outwards  from 
the  torcular,  and  then,  at  its  junction  with  the  superior 
petrosal  sinus,  forms  the  sigmoid  sinus.  The  right  lateral 
sinus  conveys  most  of  the  blood  (brought  by  the  longitudinal 
sinus)  from  the  cortex,  while  the  left  lateral  sinus  conveys 
that  brought  by  the  straight  sinus  from  the  central  ganglionic 
regions. 

The  SIGMOID  SINUS  pursues  a  tortuous  course  along  the 
posterior  wall  of  the  petrous,  and  ends,  after  making  an  almost 
complete  circle  and  forming  the  jugular  bulb,  in  the  internal 
jugular  vein.  The  tortuous  course,  formation  of  the  bulb 
which  rests  on  a  prominence  of  bone,  and  the  comparatively 
narrow  mouth  of  the  jugular  vein,  are  all  factors  in  preventing 


28  SURGICAL  ANATOMY 

the  aspiration  of  this  and  the  other  communicating  sinuses  on 
inspiration.  As  the  sinuses  are  rigid  channels,  they  would 
otherwise  be  easily  aspirated  by  the  suction  action  of  in- 
spiration, anaemia  of  the  brain,  with  consequent  uncon- 
sciousness, resulting.  This  does  occur  in  some  individuals  in 
whom  the  bony  prominence  under  the  jugular  bulb  is  wanting, 
when  a  long  breath  is  taken  suddenly.  Normally,  however, 
the  flow  is  arrested  during  inspiration  by  the  flattening  of 
the  bulb  upon  the  bony  projection,  while  the  inferior  petrosal 
sinus,  acting  as  an  injector,  rapidly  restarts  the  flow  once 
inspiration  is  at  an  end. 

As  the  sigmoid  sinus  is  in  close  relationship  to  the  mastoid 
antrum,  it  frequently  suffers  from  pyogenic  thrombosis  by 
extension  of  the  septic  process.  Where  the  mastoid  antrum 
is  large,  it  sometimes  extends  under  the  sigmoid  sinus,  and 
comes  directly  into  relationship  with  the  cerebellum,  cerebellar 
abscess  thus  occasionally  arising  from  mastoid  disease,  without 
previous  sigmoid  sinus  thrombosis. 

The  emissary  mastoid  vein  leaves  the  sigmoid  sinus  just 
beyond  its  commencement,  and  not  infrequently  conveys 
septic  mischief  to  it  from  the  outside.  The  dome  of  the 
jugular  bulb  is  situated  directly  under  the  middle  ear. 

The  STRAIGHT  SINUS  runs  along  the  junction  of  the  falx  with 
the  tentorium,  from  the  inferior  longitudinal  sinus  to  the  left 
lateral  sinus,  near  the  torcular.  It  conveys  blood  from  the 
inferior  longitudinal  sinus  and  also  from  the  interior  of  the 
brain,  brought  to  it  by  the  veins  of  Galen,  which  emerge  from 
under  the  corpus  callosum.  These  veins  are  believed  to  take 
part  in  removing  cerebro-spinal  fluid  from  the  ventricles  of 
the  brain,  and  hence  obstruction  of  the  veins  may  be  a  cause 
of  hydrocephalus. 

The  brain  derives  its  blood-supply  from  the  vertebral  and 
internal  carotid  arteries,  after  these  have  anastomosed  at 
the  CIRCLE  OF  WILLIS.  This  circle  is  formed  posteriorly  by 
the  basilar  (from  junction  of  the  two  vertebrals),  which  gives 
off  the  two  posterior  cerebral  arteries,  which  in  turn  supply 
the  two  posterior  communicating  branches  of  the  circle, 
which  join  the  internal  carotids. 

The  internal  carotids  are  continued  up  as  the  middle 
cerebral  arteries,  but  give  off  anteriorly  the  anterior  cere- 
bral arteries,  which  communicate  with  each  other  through 


THE  HEAD  29 

the  anterior  communicating  artery,  thus  completing  the 
circle. 

The  anterior,  middle,  and  posterior  CEREBRAL  VESSELS 
form  a  rich  vascular  network  in  the  pia  mater,  which  is  a  thick 
flocculent  membrane  enveloping  the  brain  and  dipping  into 
the  sulci.  From  it  the  cortical  vessels  run  vertically  into  the 
brain,  through  the  grey  matter,  to  terminate  in  the  white 
matter.  These  vessels  do  not  anastomose,  and  are  thus  end 
arteries.  The  middle  cerebral  is  of  most  importance,  and 
runs  in  the  fissure  of  Sylvius,  giving  off  inner  and  outer 
striate  branches  to  the  lenticular  and  caudate  nuclei  and  optic 
thalamus,  all  of  which  pass  through  the  internal  capsule. 
These  vessels,  in  common  with  other  small  vessels  supplying 
the  internal  nuclei,  are  frequently  affected  by  arterio-sclerosis 
and  aneurysms,  which  may  be  multiple  (miliary  aneurysms 
of  Charcot),  and  one  of  the  outer  striate  branches  going  to 
the  caudate  nucleus,  which  is  larger  than  its  neighbours, 
is  a  frequent  source  of  cerebral  haemorrhage.  The  middle 
cerebral  also  supplies  branches  to  the  motor  area  (all  but  a 
small  portion  of  the  leg  area  supplied  by  the  anterior  cerebral) 
and  the  centres  for  hearing,  motor  speech,  and  part  of  that 
for  vision.  This  vessel  is  the  usual  source  of  CEREBRAL 
HAEMORRHAGE,  or  apoplexy,  generally  from  rupture  of  a  small 
aneurysm.  If  small,  the  haemorrhage  forms  a  localized  clot 
in  the  brain  substance,  while  if  large,  it  may  extend  over  a 
large  area  of  the  surface,  giving  rise  to  compression,  or  may 
burst  into  the  lateral  ventricle. 

Rupture  of  one  of  the  striate  branches  generally  affects 
the  internal  capsule,  and  in  these  cases,  although  the  lesion 
may  be  small,  the  effect  is  generally  a  hemiplegia  owing  to 
the  crowding  of  the  motor  fibres.  Cerebral  embolism  is 
followed  by  softening  of  the  brain  substance,  where  the 
smaller  central  arteries  are  affected,  but  is  less  often  complete 
when  the  vessels  supplying  the  cortical  area  are  affected 
owing  to  the  pial  anastomosis.  Embolism  has  followed  the 
manipulation  and  treatment  of  carotid  aneurysm  from  detach- 
ment of  clots,  and  where  one  of  the  large  vessels  is  blocked 
paralysis  or  death  may  result.  Owing  to  the  free  anastomosis 
of  the  cerebral  vessels,  it  is  possible  to  ligature  both  common 
carotids,  with  an  interval  of  a  few  weeks  between  them,  the 
circulation  being  carried  on  by  the  vertebrals. 


30  SURGICAL  ANATOMY 

The  anastomosis,  together  with  the  markedly  tortuous  course 
of  the  large  vessels  and  small  size  of  the  vessels  entering  the 
brain,  diminishes  the  pulsation  affecting  the  brain  substance. 
The  larger  cerebral  vessels  have  no  companion  veins,  the 
blood  being  returned  by  the  sinuses.  The  small  superfical 
veins  discharge  their  blood  into  the  superior  longitudinal, 
lateral,  and  cavernous  sinuses,  while  the  small,  deep  veins 
from  the  interior  of  the  brain  empty  into  the  straight  sinus. 

The  mesencephalon  is  about  f  inch  long,  and  occupies  the 
aperture  in  the  tentorium  cerebelli  connecting  the  cerebrum 
above  with  the  pons,  etc.,  below.  It  presents  the  corpora 
quadrigemina  dorsally  and  the  large  CRURA  CEREBRI  ventrally, 
which  gradually  converge  to  enter  the  pons.  Each  crus  is 
encircled  by  the  optic  tract  at  its  point  of  emergence  from 
the  cerebrum.  Each  crus  consists  of  a  tegmentum,  or  dorsal 
portion,  which  contains  sensory  fibres  running  to  the  region 
of  the  optic  thalamus.  and  a  crusta,  or  ventral  portion,  which 
contains  the  motor  fibres  which  have  descended  from  the 
cortex  through  the  corona  radiata  and  internal  capsule  to 
reach  it.  Haemorrhage  into  the  crusta  causes  hemiplegia 
of  the  opposite  side  of  the  body,  and,  when  on  the  inner 
margin,  paralysis  of  the  third  nerve  on  the  side  of  the  lesion. 

The  cerebellum  lies  under  the  tentorium,  which  separates 
it  from  the  under  surface  of  the  cerebrum,  and  behind  the  pons 
and  medulla.  It  consists  of  two  lateral  hemispheres  and  a 
median  portion,  the  vermis,  and  is  also  divided  into  upper  and 
lower  portions  by  the  great  horizontal  fissure.  It  is  composed 
of  grey  matter  externally,  and  white  matter  internally,  with 
several  grey  nuclei  embedded  in  it.  It  is  connected  with  the 
brain,  pons,  and  medulla  by  three  peduncles.  The  SUPERIOR 
PEDUNCLES  contain  efferent  fibres,  which  extend  upwards  on 
the  dorsum  of  the  pons  to  the  inferior  quadrigeminal  bodies. 
They  converge  as  they  ascend,  forming  first  the  lateral 
boundaries  and  later  the  roof  of  the  fourth  ventricle,  and  they 
are  concealed  from  view  by  the  overlapping  cerebellum. 
The  MIDDLE  PEDUNCLES  are  the  largest,  and  contain  both 
afferent  and  efferent  fibres,  which  connect  the  cerebellum 
with  the  pons.  The  INFERIOR  PEDUNCLES  also  contain  both 
afferent  and  efferent  fibres,  and  consist  of  the  restiform  body 
of  the  medulla  continued  upwards  over  the  pons  and  then 
turned  backwards  to  the  cerebellum.  The  direct  cerebellar 


THE  HEAD  31 

tract  forms  the  greater  portion  of  the  afferent  fibres  in  the 
inferior  peduncle,  which  cross  chiefly  to  the  opposite  side  of 
the  cerebellar  cortex.  The  efferent  fibres  of  the  inferior 
peduncle  form  the  cerebello-olivary-tract,  connecting  the  cere- 
bellum with  the  medulla.  The  cerebellum  is  not  always 
confined  to  the  cranial  cavity,  but  often  extends  through  the 
foramen  magnum,  wrapping  round  the  medulla  and  even  the 
upper  extremity  of  the  cord. 

The  pons  is  situated  between  the  crura  cerebri  and  the 
medulla,  its  ventral  surface  being  composed  of  the  transverse 
fibres  of  the  middle  cerebellar  peduncles,  which  sweep  across 
it  from  side  to  side.  This  ventral  surface  lies  in  contact  with 
the  dorsum  sellse  of  the  sphenoid  and  basilar  process  of  the 
occipital  bone,  and  presents  a  median  groove,  which  lodges  the 
basilar  artery  and  twx)  lateral  eminences,  due  to  the  underlying 
masses  of  the  pyramidal  tract  passing  from  the  crura  cerebri 
above  to  the  medulla  below.  The  fifth  nerve  emerges  near  its 
upper  margin,  while  the  sixth,  seventh,  and  eight  nerves 
emerge  at  its  lower  border.  The  dorsal  aspect  of  the  pons, 
together  with  that  of  the  medulla,  presents  the  lozenge-shaped 
FOURTH  VENTRICLE,  which  is  roofed  in  by  the  thin  superior 
and  inferior  medullary  vela,  which  proceed  outwards  from 
the  white  centre  of  the  cerebellum,  and  run  respectively  up 
and  down,  covering  the  ventricle  with  a  peaked  roof.  The 
inferior  velum  is  deficient  at  its  lower  border,  and  presents 
an  opening,  the  FORAMEN  OF  MAGENDIE,  which  permits  of 
communication  between  the  fourth  ventricle  and  the  subarach- 
noid  space,  similar  openings  occurring  at  the  apices  of  the 
lateral  recesses,  which  project  laterally  from  the  widest  part 
of  the  space,  and  curve'  round  the  upper  parts  of  the  restiform 
bodies  (foramina  of  Key  and  Retzius).  The  fourth  nerves 
issue  from  the  substance  of  the  superior  velum  close  to  the 
inferior  quadrigeminal  bodies.  The  striae  acoustics  cross  the 
floor  of  the  ventricle  transversely,  and  make  the  distinction 
between  the  pontine  and  medullary  portions,  and  possibly 
connect  the  cochlear  nucleus  with  the  cerebellum. 

The  medulla  is  about  i  inch  long,  conical  in  shape,  being 
broader  above,  and  connects  the  pons  with  the  cord.  In 
direction  it  is  vertical,  and  it  ends  about  the  foramen  magnum, 
the  ventral  surface  lying  on  the  basilar  portion  of  the  occipital 
bone,  while  the  dorsal  and  lateral  surfaces  are  largely  covered 


32  SURGICAL  ANATOMY 

by  the  cerebellum.  The  median  furrow  on  the  ventral  surface 
commences  as  a  blind  depression,  the  foramen  caecum,  at  the 
lower  border  of  the  pons,  and  ends  at  the  decussation  of  the 
pyramids.  The  posterior  median  furrow  commences  about 
half-way  down  by  the  approximation  of  the  boundaries  of 
the  fourth  ventricle.  From  the  antero-lateral  furrow  the 
root  branches  of  the  twelfth  nerve  emerge,  while  from  the 
postero-lateral  furrow  emerge  those  of  the  ninth,  tenth,  and 
eleventh  nerves.  Between  the  anterior  median  and  lateral 
furrows  lies  the  pyramid  containing  the  motor  strands, 
which  break  up  lower  down  into  direct  and  crossed  pyra- 
midal tracts,  the  former  going  directly  down  the  anterior 
column  of  the  cord,  while  the  latter  crosses  at  the  decussation 
of  the  pyramids,  to  enter  the  crossed  pyramidal  tract  in  the 
postero-lateral  portion  of  the  cord.  The  lateral  surface  of 
the  medulla  presents  the  olive  lying  outside  the  pyramid, 
which  is  formed  by  the  underlying  inferior  olivary  nucleus. 
The  posterior  surface  presents  the  funiculi  gracilis  and  cuneatus, 
in  which  the  columns  of  Goll  and  Burdach  respectively  ter- 
minate in  the  gracile  and  cuneate  nuclei.  External  to  these 
lies  the  tubercle  of  Rolando,  formed  by  the  substantia  gela- 
tinosa  Rolandi,  which  caps  the  posterior  horn  coming  to  the 
surface,  while  at  the  upper  extremity  of  this  posterior  surface 
is  the  restiform  body,  which  forms  the  inferior  cerebellar 
peduncle,  and  in  which  the  direct  cerebellar  tract  runs  to  the 
cerebellum.  The  medulla  contains  the  nuclei  of  all  the  cranial 
nerves  after  the  fourth  ;  the  cardiac,  respiratory,  and  vaso- 
motor  centres ;  those  for  vomiting,  deglutition,  etc. ;  those 
governing  the  sweat,  lachrymal,  and  salivary  secretions,  and 
centres  for  winking  and  dilatation  of  the  pupil. 

The  cord,  is  partially  divided  by  anterior  and  posterior 
median  clefts,  the  former  being  generally  much  shallower 
and  broader  than  the  latter,  and  containing  a  fold  of  pia  mater 
not  presented  by  the  latter.  There  is  no  antero-lateral  sulcus 
along  the  line  of  emergence  of  the  anterior  nerve  roots,  but  the 
postero-lateral  sulcus  from  which  the  posterior  roots  emerge 
is  marked.  The  columns  of  Goll  and  Burdach  occupy  the 
posterior  surface  between  the  median  fissure  and  postero- 
lateral  sulcus,  the  former  placed  internally  to  the  latter,  from 
which  it  is  separated  in  the  cervical  region  by  the  posterior 
paramedian  groove  containing  a  process  of  pia  mater.  The 


THE  HEAD  33 

grey  matter  in  each  half  forms  a  crescentic  mass  with  a  blunt 
anterior    and   long   posterior   horns,    the    two    halves    being 
connected  by  a  grey  commissure  containing  the  central  canal, 
an  anterior  white  commissure  lying  in  front  of  the  grey  one. 
The  anterior  cornua  contain  the  large  multipolar  nerve  cells 
from  which  the  motor  nerves  originate,  and  which  form  their 
trophic  centres,  just  as  the  cells  in  the  cortex  govern  the 
motor  tracts  in  the  cord.     The  posterior  cornua  receive  the 
sensory  fibres,  which  have  already  passed  through  a  ganglion 
before  entering  the  cord.     Clarkz's  column  consists  of  a  cell 
group  situated  in  the  posterior  horn  of  grey  matter  in  the 
dorsal  region.    The  substantia  gelatinosa  Rolandi  is  a  V-shaped 
mass  capping  the  posterior  horn  in  the  cervical  and  dorsal 
regions.     The  course  of  SENSORY  FIBRES  is  doubtful.     Pro- 
bably many  first  enter  Burdach's  column  and  divide  into  a 
short   descending   and  long   ascending  fibre.     The  latter  is 
gradually  displaced  inwards   by   fibres   from    other   nerves, 
until   it   enters   Goll's   column   and   ends   ultimately  in   the 
medulla.   Other  fibres  probably  enter  Clarke's  column,  possibly 
first  crossing  to  the  opposite  side,  whence  fibres  pass  to  the 
direct  cerebellar  tract  and  Gower's  comma  tract  (two  super- 
ficial tracts  lying,  the  former  postero -laterally,  and  the  latter 
antero-laterally).      The   direct   cerebellar  tract   runs   to   the 
cerebellum,  while  Gower's  tract  probably  does  likewise,  after 
passing  through  the  formatio  reticularis.     The  sensory  tracts, 
after   passing   through   the   medulla   and   pons,  occupy   the 
tegmentum  of  the  crus,  and  the  posterior  third  of  the  posterior 
limb  of  the  internal  capsule,  and  then  pass  to  the  cortex, 
particularly  of  the  occipital  region,  through  the  corona  radiata. 
The  direct  pyramidal  tracts  descend  on  either  side  of  the 
median  anterior  fissure,   while  the  crossed  pyramidal  tract 
lies  in  front  of  the  posterior  horn.     The  MOTOR  TRACTS  run 
from  the  cortex  of  the   Rolandic  area  through  the  corona 
radiata,    anterior   two-thirds   of   the   posterior   limb    of   the 
internal  capsule,  crusta  of  the  crus,  pons,  and  medulla,  where 
most  of  the  fibres  cross  to  enter  the  crossed  pyramidal  tract, 
while  a  few  go  direct  into  the  direct  pyramidal  tract. 

Concussion  of  the  brain  consists  of  a  molecular  vibration  of 
the  brain  substance,  with  or  without  laceration,  but  with 
multiple  punctiform  ecchymoses.  The  condition  may  be 
accompanied  by  grave  symptoms  at  the  time,  or  they  may 

3 


34  SURGICAL  ANATOMY 

only  appear  at  a  later  period.  Concussion  is  a  frequent 
result  of  railway  accidents. 

Compression  may  be  caused  by  depressed  fracture,  haemor- 
rhage, abscess,  tumour,  etc.,  and  its  effects  will  depend  on 
the  extent  and  location  of  the  lesion. 

Abscesses  of  the  brain  occur  most  frequently  in  the  temporo- 
sphenoidal  lobe  or  in  the  cerebellum,  the  infection  being 
conveyed  from  the  middle  ear  in  many  instances.  It  is  note- 
worthy that  cerebral  abscesses  are  generally  accompanied 
by  low  temperature  and  slow,  full  pulse,  owing  to  the  com- 
pression of  the  brain. 

Of  the  tumours  of  the  brain,  tubercle,  if  it  may  be  called 
a  tumour,  is  the  most  common,  the  lesions  occurring  most 
frequently  about  the  base,  although  they  may  occur  at  any 
part.  Syphilomas  occur  not  infrequently,  while  of  true 
tumours  glioma  is  the  most  common.  Some  gliornas  present 
sarcomatous  elements,  and  may  ultimately  erode  and  per- 
forate the  skull,  and  present  on  the  surface  as  pulsating 
tumours.  As  tumours  grow  comparatively  slowly,  as  a  rule, 
the  brain  accommodates  itself  to  the  increasing  pressure  for 
a  considerable  period,  pressure  symptoms  only  becoming 
marked  when  the  tumour  is  getting  large.  In  such  cases, 
even  when,  from  size  or  location,  removal  of  the  tumour  is 
out  of  the  question,  the  raising  of  an  osteoplastic  skull  flap, 
so  as  to  relieve  the  pressure,  is  frequently  followed  by  marked 
benefit.  Where,  on  the  other  hand,  the  tumour  has  invaded 
some  focal  area,  such  as  the  motor  cortex,  the  patient  may  be 
subject  to  fits  of  Jacksonian  epilepsy,  which  differs  from 
ordinary  epilepsy  in  many  important  particulars,  and  which 
ftequently  affords  valuable  information  as  to  the  seat  of  the 
lesion,  from  the  fit  beginning  in,  and  sometimes  even  being 
confined  to,  the  part  (e.g.,  a  thumb)  supplied  by  the  affected 
portion  of  cortex.  In  operating  on  intracranial  tumours,  it 
is  usual,  instead  of  trephining,  to  raise  an  osteoplastic  flap 
of  superficial  soft  tissues  and  bone  in  one  piece,  so  as  to  expose 
a  considerable  surface.  After  the  operation  is  finished,  the 
osteoplastic  flap  is  replaced. 


THE  HEAD  35 

THE  CRANIAL  NERVES. 

The  olfactory  springs  externally  from  the  fissure  of  Sylvius, 
near  the  anterior  perforated  space.  As  it  is  close  to  the  third 
frontal  convolution,  it  follows  that  aphasia  from  affection  of 
Broca's  lobe  on  the  left  side  may  be  associated  with  defective 
sensation  of  smell  in  the  left  nostril.  The  nerve  may  be  com- 
pletely destroyed  by  fracture  of  the  anterior  fossa  or  by 
malignant  disease  of  the  ethmoid,  through  the  cribriform 
plate  of  which  it  passes  to  be  distributed  to  the  nasal  mucous 
membrane. 

The  optic  nerve  arises  from  the  geniculate  bodies  under  the 
optic  thalamus  and  corpora  quadrigemina,  the  TRACTS  wind- 
ing over  the  crura  cerebri  and  converging  in  front  of  the 
interpeduncular  space  to  form  the  OPTIC  COMMISSURE.  Here 
the  fibres  of  the  tracts  divide,  the  outer  half  of  each  continuing 
to  the  outer  side  of  the  corresponding  retina,  while  the  inner 
half  crosses  to  supply  the  inner  half  of  the  opposite  retina. 
Behind  these  fibres  are  others,  which  run  from  one  tract  to 
the  other,  and  are  known  as  Gudden's  commissure.  If, 
therefore,  the  entire  thickness  of  one  tract  be  affected  by  the 
pressure  of  a  tumour,  the  temporal  side  of  the  eye  on  the  same 
side  and  the  nasal  side  of  the  opposite  eye  will  be  rendered 
blind  (hemianopsia) .  If  the  OPTIC  NERVE  be  pressed  on, 
however,  as  by  a  tumour  of  the  orbit,  there  will  result  com- 
plete blindness  of  both  sides  of  the  affected  eye,  probably 
associated  with  affections  of  the  third,  fourth,  and  sixth  nerves, 
which  lie  close  to  it. 

The  third  nerve,  or  motor  oculi,  arises  in  front  of  the  pons, 
near  the  posterior  perforated  spot,  lies  on  the  outer  wall  of 
the  cavernous  sinus,  and,  dividing  into  two  branches,  enters 
the  orbit  through  the  sphenoidal  fissure  between  the  heads 
of  the  external  rectus.  The  action  of  the  third  nerve  is  con- 
sidered in  connection  with  the  eye.  It  affords  from  its  action 
on  the  pupil,  which  becomes  contracted  when  the  nerve  is 
irritated,  and  dilated  when  it  is  paralyzed,  a  very  delicate 
test  for  intracranial  pressure  arising  from  tumour,  haemorrhage, 
or  abscess  in  the  region  of  the  middle  fossa.  A  lesion  near 
the  Sylvian  aqueduct  might  produce  a  bilateral  paralysis  of 
the  nerves. 

The  fourth  nerve  emerges  just  behind  the  corpora  quadri- 

3—2 


36  SURGICAL  ANATOMY 

gemina.  Its  course  is  similar  to  that  of  the  third,  and  its 
action  is  discussed  with  the  eye. 

The  fifth,  or  trigeminal,  arises  from  the  surface  of  tin;  pons 
by  a  small  motor  and  large  sensory  portions.  These  proceed 
forward  in  the  posterior  fossa  of  the  base,  pierce  the  dura 
at  the  attachment  of  the  tentorium  cerebelli  to  the  superior 
border  of  the  petrous,  the  sensory  root  then  forming  the 
large  GASSERIAN  GANGLION,  which  is  lodged  in  a  small  cavity 
of  the  dura,  formed  by  a  splitting  of  its  layers,  and  called  the 
cavum  Meckelii.  The  ganglion  lies  in  a  depression  on  the  apex 
of  the  petrous,  and  divides  into  its  three  branches — ophthal- 
mic, superior,  and  inferior  maxillary,  the  motor  root  joining 
the  latter.  The  OPHTHALMIC  DIVISION  pursues  a  course 
similar  to  the  third  nerve,  and  breaks  up  into  frontal,  nasal, 
and  lachrymal  branches,  the  nasal  branch  supplying  the 
sensory  root  to  the  LENTICULAR  GANGLION,  which  ganglion 
supplies  the  short  ciliary  nerves  to  the  ciliary  muscle  and  iris. 
Destruction  of  this  division  not  merely  destroys  reflex  blinking, 
but  removes  the  trophic  influence  of  the  nerve  on  the  parts 
supplied,  ulceration  being  apt  to  occur  in  consequence. 

The  SUPERIOR  MAXILLARY  DIVISION  passes  through  the 
foramen  rotundum,  crosses  the  spheno-maxillary  fossa,  and 
runs  under  the  floor  of  the  orbit,  to  emerge  at  the  infra-orbital 
foramen.  It  supplies  the  skin  in  the  temporal  and  malar 
regions,  and  the  teeth  and  gums,  lining  of  the  antrum,  and 
sensory  branch  to  Meckel's  ganglion.  MECKEL'S  GANGLION 
supplies  the  nasal  fossae,  roof  of  mouth,  upper  part  of  pharynx, 
tonsil,  gums,  soft  palate,  and  uvula,  etc.  ;  while  by  its  motor 
branch,  derived  from  the  vidian,  it  enervates  the  levator 
palati,  azygos  uvulae,  palato-glossus,  and  pharyngeus. 

The  INFERIOR  MAXILLARY  DIVISION  emerges  through  the 
foramen  ovale,  and  divides  into  anterior  and  posterior  trunks, 
of  which  the  anterior  is  chiefly  motor  and  supplies  all  the 
muscles  of  mastication  except  the  buccinator  (supplied  by 
the  seventh).  The  posterior  trunk  gives  off  the  auriculo- 
temporal,  which  supplies  that  region  with  sensation,  as  well 
as  the  temporo-maxillary  joint  and  parotid  gland,  and  gives 
a  sensory  root  to  the  otic  ganglion,  which  supplies  the  tensors 
tympani  and  palati.  The  trunk  also  gives  off  the  gustatory 
nerve,  which  supplies  sensation  to  the  anterior  two-thirds  of 
the  tongue.  It  is  joined  in  the  pterygoid  region  by  the 


THE  HEAD  37 

chorda  timpani,  through  which  probably  taste  fibres  are 
derived,  and  later  by  branches  of  the  hypoglossal.  The 
inferior  dental  branch  supplies  the  mylo-hyoid  and  anterior 
belly  of  the  digastric,  supplies  sensation  to  the  lower  teeth, 
and  gives  off  the  mental  branch,  which  emerges  through  the 
mental  foramen  to  supply  the  skin  of  the  lip  and  chin.  Irrita- 
tion of  this  nerve  from  dental  caries  may  cause  earache, 
while,  conversely,  placing  cotton-wool  with  a  little  laudanum 
in  the  ear  may  ease  toothache.  The  cold  of  an  ether  spray 
applied  to  the  external  auditory  meatus  may  numb  the  nerve 
and  enable  a  tooth  to  be  extracted  painlessly. 

The  Gasserian  ganglion  has  frequently  been  removed  suc- 
cessfully for  intense  trigeminal  neuralgia.  The  neuralgia  is 
believed  to  be  due  to  contraction  of  the  dural  pocket,  con- 
taining the  ganglion,  which  is  therefore  crushed.  The  ganglion 
is  best  reached  through  the  face,  antrum  of  Highmore,  spheno- 
maxillary  fossa,  and  foramina  rotundum  and  ovale  (see  under 
Middle  Fossa  of  Skull),  but  may  also  be  reached  through  the 
skull  from  above,  or  through  the  pterygoid  region.  Tic 
douloureux  is  a  term  frequently  applied  to  trigeminal  neuralgia, 
not  necessarily  involving  all  the  divisions.  Where  only  one 
division  is  affected,  it  may  be  due  to  peripheral  irritation, 
such  as  dental  caries,  or  inflammation  at  the  point  of  exit 
from  one  of  the  osseous  canals.  In  such  cases  a  small  peri- 
pheral operation  may  be  sufficient. 

The  supra-orbital  foramen  is  situated  at  the  junction  of 
the  inner  and  middle  thirds  of  the  supra-orbital  margin,  and 
a  line  drawn  from  that  point  to  the  interval  between  the 
bicusp  teeth  of  both  jaws  (Holderis  line)  passes  through  the 
infra- orbital  foramen,  and,  if  prolonged,  through  the  mental 
foramen. 

The  supra- orbital  nerve  is  reached  by  a  small  horizontal 
incision  just  above  the  orbital  margin,  with  its  centre  on  the 
line.  The  infra-orbital  nerve  is  reached  by  a  similar  incision 
fully  J  inch  below  the  lower  margin  of  the  orbit,  with  its 
centre  on  the  line,  the  orbicularis  and  levator  labii  superioris 
being  cut  through.  The  mental  nerve  is  reached  likewise  by 
a  similar  incision,  with  its  centre  on  the  line  midway  between 
the  upper  and  lower  margins  of  the  lower  jaw.  The  depressor 
anguli  oris  and  labii  inferioris  are  cut,  and  the  nerve  exposed 
and  treated  either  by  stretching  or  by  cutting.  The  lingual 


38  SURGICAL  ANATOMY 

nerve  may  be  reached  by  an  incision  through  the  mucous  mem- 
brane a  little  below  and  behind  the  last  molar  tooth.  The 
inferior  dental  nerve  is  reached  through  a  vertical  incision  in 
the  mucous  membrane  of  the  mouth,  above  and  in  front  of 
the  internal  pterygoid,  the  muco-periosteum  being  shelled, 
and  the  nerve  caught  as  it  enters  the  dental  foramen.  It  may 
also  be  treated  through  an  external  incision,  the  ascending 
ramus  being  trephined. 

The  sixth  nerve  arises  from  the  floor  of  the  fourth  ventricle, 
and  emerges  between  the  anterior  pyramid  and  pons.  It  lies 
to  the  inner  side  of  the  cavernous  sinus,  but  otherwise  has  a 
course  similar  to  the  third.  Its  action  is  discussed  under  the 
Eye. 

The  seventh,  or  facial,  nerve  arises  with  the  sixth  from  the 
floor  of  the  fourth  ventricle,  and  emerges  between  the  olive 
and  restiform  body.  It  enters  the  internal  auditory  meatus 
with,  but  above,  the  auditory  nerve,  traverses  the  Fallopian 
aqueduct,  and  emerges  at  the  stylo-mastoid  foramen,  whence 
it  passes  through  the  parotid  gland  and  forms  the  pes 
anserinus. 

A  partial  decussation  of  the  facial  nerve  occurs  in  the  pons 
at  the  level  of  the  apparent  origin  of  the  fifth  nerve.  If  a 
unilateral  lesion  occur  in  the  pons  anterior  to  this  position, 
the  face  will  be  paralyzed  on  the  same  side  as  the  rest  of  the 
body,  a  complete  hemiplegia  resulting  on  the  side  opposite 
to  that  of  the  lesion.  If,  on  the  other  hand,  the  lesion  be 
below  the  level  of  this  crossing,  the  face  will  be  paralyzed  on 
the  same  side  as  the  lesion,  whereas  the  paralysis  of  the  rest 
of  the  body  will  still  be  on  the  opposite  side  (the  decussation 
of  the  pyramids  occurring  lower  down,  in  the  medulla). 

In  the  petrous  portion  it  gives  off  the  great  petrosal,  which 
runs  to  Meckel's  ganglion  through  the  vidian,  and  also  the 
chorda  tympani,  which  leaves  the  tympanic  cavity  through 
the  Glaserian  fissure  to  supply  the  transverse  lingual  muscle, 
and  ultimately  joins  the  gustatory,  to  which  it  probably 
conveys  taste  fibres.  Owing  to  the  chorda  supplying  the 
transverse  iingualis,  which  protrudes  the  tongue  on  its  own 
side,  a  patient  with  facial  paralysis  protrudes  the  tongue 
toward  the  affected  side. 

The  facial  nerve  supplies  the  muscles  of  the  face,  and  also 
the  buccinator.  When  the  trunk  is  paralyzed,  the  paralysis 


THE  HEAD  39 

of  one  side  of  the  face  is  absolute :  the  patient  cannot  close 
the  eye/  the  cornea  accordingly  becoming  affected  ;  the  tears 
drop  on  to  the  cheek  ;  the  mouth  is  drawn  to  the  affected  side  ; 
and  saliva  dribbles  from  the  affected  corner.  Food  lodges 
in  the  cheek  from  paralysis  of  the  buccinator,  and  the  patient 
cannot  whistle. 

A  peripheral  lesion  of  the  nerve  may  also  arise  from  cold 
(Bell's  paralysis). 

Where  the  centre  is  affected  the  paralysis  is  generally  not 
absolute,  the  mimetic  play  of  the  features  being  maintained. 

The  nerve  may  be  reached  through  an  incision  ij  inches 
long,  from  the  anterior  margin  of  the  mastoid  process,  at  the 
level  of  the  external  auditory  meatus,  to  a  point  just  behind 
the  angle  of  the  lower  jaw.  The  sterno-mastoid  is  drawn 
backwards,  and  the  parotid  gland  pulled  forwards,  the  pos- 
terior belly  of  the  digastric  pulled  downwards,  and  the  nerve 
exposed  at  the  upper  part  of  the  wound  and  stretched.  The 
operation  may  be  done  for  facial  spasm.  In  some  cases  of 
facial  paralysis,  due  to  destruction  of  part  of  the  nerve,  the 
peripheral  portion  has  been  united  to  the  spinal  accessory, 
the  result,  however,  not  being  altogether  fortunate,  even  when 
successful  so  far  as  restoration  of  motor  function  is  concerned, 
as  the  face  muscles  must  then  work  in  conjunction  with  those 
supplied  by  the  spinal  accessory. 

The  eighth,  or  auditory,  nerve  arises  in  the  floor  of  the  fourth 
ventricle,  and  emerges  between  the  olive  and  restiform  body, 
to  pass  to  the  internal  auditory  meatus  below  the  facial. 
It  supplies  the  auditory  apparatus. 

The  ninth,  or  glosso-pharyngeal,  nerve  arises  in  the  fourth 
ventricle,  emerges  between  olive  and  restiform  body,  and 
leaves  the  skull  by  the  jugular  foramen  to  supply  sensation  to 
the  pharynx,  and  the  posterior  part  of  the  tongue  with  taste. 
It  gives  branches  to  the  stylo-pharyngeus  and  tonsil. 

The  tenth,  vagus,  or  pneumogastrie,  arises  and  emerges  like 
the  ninth,  and  also  leaves  the  skull  through  the  jugular  fora- 
men, giving  off  the  auricular  or  Arnold's  nerve  as  it  does  so, 
which  passes  through  the  petrous  and  supplies  the  skin 
behind  the  pinna  and  the  lining  of  the  auditory  meatus. 
Moistening  the  skin  of  this  region  with  water  is  supposed 
to  convey  stimulus  to  the  pneumogastrie,  which  would  urge 
it  to  renewed  exertion  after  a  heavy  dinner.  Foreign  bodies 


40 


SURGICAL  ANATOMY 


in  the  ear  frequently  cause  uncontrollable  cough  from  irrita- 
tion conveyed  along  Arnold's  nerve  to  the  superior  laryngeal 
branch  of  the  vagus.  This  laryngeal  branch  leaves  the  trunk 
after  it  has  been  joined  by  the  accessory  portion  of  the  spinal 
accessory,  runs  down  and  forwards  beneath  the  internal 


FIG.  4. — CORONAL  HEAD  SECTION  PASSING  THROUGH  MIDDLE  EAR. 

Above,  the  superior  longitudinal  sinus  and  falx  cerebri  are  seen. 

Note  in  the  brain  the  corpus  callosum,  the  anterior  horns  of  the  lateral  ventricles,  and 
optic  thalami. 

The  temporo-sphenoidal  lobes  are  shown  resting  on  the  thin  tegmen  tympani.  The  attic 
of  the  tympanum  is  well  shown,  as  likewise  the  tympanum  occupied  by  part  of  the  ossicles 
and  a  portion  of  the  external  auditory  meatus. 

Note  in  particular  the  entrance  of  the  seventh  and  eighth  nerves  into  the  internal  ear. 

carotid,  to  supply  the  crico-thyroid  muscle  and  laryngeal 
mucous  membrane.  Irritation  of  the  nerve  causes  spasm  of 
the  glottis. 

The  recurrent  laryngeal  branch  passes  round  the  first  part 
of  the  subclavian  on  the  right  and  the  transverse  aorta  on 


THE  HEAD  41 

the  left  .and  runs  up  to  enter  the  lower  and  back  part  of  the 
larynx,  and  supply  all  the  muscles  except  the  crico-thyroid. 

Pressure  on  the  nerve  causes  cough.  Pressure  on  both 
nerves  causes  complete  loss  of  voice,  but  no  shortness  of 
breath. 

The  vagus  nerves  supply  the  lungs,  heart,  and  the  stomach, 
and  communicate  with  the  great  sympathetic  plexuses. 
Irritation  of  the  terminal  filaments  supplying  the  stomach 
frequently  cause  "  stomach  cough." 

The  spinal  accessory,  or  eleventh  nerve,  consists  of  an 
accessory  part,  which  arises  like  the  vagus  and  ultimately 
blends  with  it,  and  a  spinal  part,  which  arises  from  the  anterior 
cornu  of  the  cord,  and  ascends  to  enter  the  skull  by  the  fora- 
men magnum,  and  leave  it  again  with  the  vagus.  It  passes 
down  and  backwards  through  the  sterno-mastoid,  which  it 
supplies  in  part,  and  ends  in  the  trapezius. 

The  nerve  is  associated  with  phonation,  the  accessory  por- 
tion supplying  the  motor  filaments  in  the  vagus,  while  the 
spinal  part  controls  the  muscles  mentioned.  Stretching  or 
cutting  of  the  nerve  may  be  necessitated  in  spasmodic  torti- 
collis. An  incision  2j  inches  long  is  made  from  the  apex 
of  the  mastoid  process,  along  the  anterior  border  of  the  sterno- 
mastoid.  The  anterior  border  of  the  muscle  is  defined  and 
turned  up,  and  the  nerve  treated  as  it  reaches  the  muscle  on 
its  under  surface.  The  transverse  process  of  the  atlas  forms 
a  useful  guide  to  the  nerve. 

The  twelfth,  or  hypoglossal,  nerve  arises  from  the  floor  of 
the  fourth  ventricle,  and  emerges  between  the  anterior 
pyramid  and  olive.  Leaving  the  skull  through  the  anterior 
condylar  foramen,  it~  descends  with  the  vagus  to  the  level  of 
the  angle  of  the  jaw,  and  then  passes  forwards,  over  the 
carotid  vessels  and  hyo-glossus  muscle,  to  pass  beneath  the 
posterior  tendon  of  the  digastric  and  the  mylo-hyoid,  and 
end  in  the  genio-hyo-glossus.  It  supplies  the  extrinsic 
muscles  of  the  tongue,  and  gives  off  a  descending  branch  to 
supply  the  depressors  of  the  hyoid  bone. 

In  paralysis  of  the  nerve  the  tongue,  on  protrusion,  turns 
to  the  affected  side. 

BULBAR  PARALYSIS,  also  known  as  Duchenne's  paralysis,  or 
labio-glosso-pharyngeal  paralysis,  consists  of  disease  of  the 
medulla  affecting  the  origins  of  the  seventh,  ninth,  tenth, 


42  SURGICAL  ANATOMY 

eleventh,  and  twelfth  nerves,  and  is  a  very  serious  affection. 
Speech  is  affected,  the  lips  and  tongue  are  paretic,  mastica- 
tion and  swallowing  are  difficult  or  impossible,  and  the  face 
is  also  paretic. 

THE  EAR. 

The  pinna  may  be  congenitally  absent,  malformed,  or 
abnormally  small  (microtia)  or  large  (macrotia).  Small 
fistulae  may  be  found,  due  to  failure  in  fusion  of  the  various 
tubercles  from  which  the  embryonic  ear  is  formed,  and  of 
greater  consequence  is  imperfect  closure  of  the  first  branchial 
cleft,  from  which  the  external  auditory  meatus,  middle  ear, 
and  Eustachian  tube  are  formed.  Where  the  cleft  is  not 
closed  it  may  present  as  a  fissure,  commencing  either  at  the 
tragus  or  helix,  and  extending  perhaps  into  the  middle  ear, 
the  membrana  tympani  being  defective  or  even  absent. 
Sometimes  a  small  tubercle  is  found  near  the  upper  extremity 
of  the  helix  presenting  a  tuft  of  hair.  It  is  known  as  Darwin's 
tubercle,  and  is  supposed  to  represent  the  tip  of  the  tapering 
ear  of  lower  animals.  Supernumerary  auricles,  small  and 
ill-formed,  are  rarely  found  on  the  cheek  or  side  of  the  neck. 
The  subcutaneous  tissue  on  the  outer  aspect  of  the  pinna  is 
dense  and  closely  adherent  to  the  perichondrium,  and  hence 
inflammatory  processes  in  this  position  are  generally  small, 
but  very  painful.  Tophi,  or  gouty  deposits  of  urate  of  soda, 
are  sometimes  found  along  the  margin  of  the  helix. 

Extravasations  of  blood  (othaematoma)  occur  not  infre- 
quently on  the  outer  aspect  of  the  pinna,  sometimes  from 
injury  and  at  others  spontaneously,  the  latter  being  found 
particularly  in  the  insane,  and  due  probably  to  disease  of  the 
vessels.  The  extravasated  blood  is  generally  absorbed,  but 
its  absorption  is  frequently  accompanied  by  deformity  of  the 
pinna,  and  hence  it  is  sometimes  desirable  to  evacuate  such 
collections  soon  after  their  formation.  Notwithstanding  its 
generous  blood-supply  from  the  temporal  and  posterior 
auricular  arteries,  the  pinna  is  a  frequent  seat  of  frost-bite, 
owing  to  its  exposed  position  and  the  absence  of  fatty  tissue 
over  its  vessels. 

The  pinna  and  cartilaginous  meatus  are  very  firmly  adherent 
to  the  skull,  sufficiently  in  some  cases  to  bear  the  weight  of 
the  body.  Even  where,  however,  the  pinna  has  been  almost 


THE  EAR  43 

detached,  it  will,  as  a  rule,  rapidly  heal  if  stitched  in  position. 
The  sfan  under  the  lobule  of  the  ear  is  a  frequent  site  of 
sebaceous  cysts.  The  glands  in  this  region  are  not  infrequently 
enlarged  from  irritation  of  the  scalp  due  to  phtheiriasis,  and 
eczematous  conditions  of  the  external  ear. 

The  external  auditory  meatus,  rather  over  an  inch  in  length, 
has  a  wall  lined  with  skin,  which  is  composed  of  cartilage 
over  rather  more  than  the  outer  half,  and  of  bone  over  the 
remainder.  It  is  directed  forwards  and  inwards,  and  is 
curved,  with  the  convexity  pointing  upwards  and  backwards, 
so  that  both  osseous  and  cartilaginous  portions  are  directed 
downwards.  When  introducing  a  speculum,  therefore,  the 
pinna  should  be  held  upwards  and  backwards,  so  as  to  bring 
the  cartilaginous  canal  into  line  with  the  osseous.  The 
narrowest  point  is  at  the  junction  of  cartilaginous  and  osseous 
parts.  In  the  infant  the  meatus  is  shorter,  straighter,  and 
almost  entirely  cartilaginous.  The  wall  of  the  meatus  presents 
certain  gaps  on  its  anterior  and  lower  aspect,  filled  with 
fibrous  tissue  (fissures  of  Santorini).  Through  these  a 
parotid  abscess  may  burst  into  the  external  ear.  The  osseous 
wall,  owing  to  its  close  relationship  anteriorly  to  the  condyle 
of  the  jaw,  is  sometimes  fractured  by  falls  or  blows  on  the 
chin.  The  skin  of  the  meatus  is  very  adherent  to  the  under- 
lying structures,  particularly  over  the  osseous  portion,  and 
is  furnished  over  the  cartilaginous  part  with  hairs  and  ceru- 
minous  glands.  Accumulations  of  wax  secreted  by  these 
glands  is  a  frequent  cause  of  deafness.  The  osseous  portion 
of  the  canal,  in  common  with  the  back  of  the  pinna,  is  supplied 
by  the  auricular  branch  of  the  vagus,  and  hence  irritation  of 
this  part  from  wax-  or  foreign  bodies  frequently  causes  cough- 
ing, and  may  cause  vomiting,  yawning,  sneezing,  or  even 
epileptiform  attacks.  Abscesses  in  this  region  are  generally 
very  localized  and  extremely  painful,  being  affected  by  every 
movement  of  the  jaw  in  chewing  or  even  in  speaking.  Polypi 
not  infrequently  are  found  in  the  external  auditory  meatus, 
and  may  be  removed  by  snaring.  Care  should,  however, 
be  taken  not  to  mistake  masses  of  granulation  tissue  springing 
from  the  cerebral  dura,  and  protruding  through  the  thin  layer 
of  bone  separating  dura  and  meatus,  for  polypi.  If  such  be 
avulsed,  the  way  is  laid  open  for  dural  or  even  cerebral  pyogenic 
implication,  and  death  has  sometimes  resulted  from  such 


44 


SURGICAL  ANATOMY 


mistakes.    Exostoses  occasionally  occur  in  the  osseous  portion. 
They  are  generally  of  the  ivory  type  and  of  slow  growth. 

The  tympanic  membrane  in  the  infant  lies  almost  horizontally, 
and  is  attached  peripherally  to  a  separate  ring  of  bone,  which 
is  complete  save  in  its  upper  segment.  In  the  adult  the 
membrane  is  nearly  vertical,  but  is  inclined  from  above  and 
behind  downwards,  forwards  and  inwards,  so  that  its  anterior 
and  inferior  edges  form  acute  angles  with  the  meatal  wall. 


FIG.  5. — TEMPORAL  BONE. 


T.  Tegmen  tympani. 

2.  Iter. 

3.  Tegmen  antri 

4.  Accessory  antrum. 

5.  Tensor  tympani. 

6.  Processuscochleariformis. 

7.  Eustachian  tube. 
Mastoid  antrum. 


10.  Chorda  tympani. 

1 1.  Tympanic  membrane  and  handle  of  malleus . 

12.  Superior  semicircular  canal. 

13.  Fenestra  ovalis  and  stapes. 

14.  Fenestra  rotunda. 

15.  Promontory  with  Jacobson's  nerve  ramify- 

ing over  it. 

16.  Facial  canal. 


9.  Is  placed  on  bone  of  the  facial  canal,  which  conceals  the  pyramid  containing  the  stapedius 
muscle.     To  the  left  of  the  figure  are  the  head  of  the  malleus  and  long  process  of  the 


It  is  composed  of  fibrous  tissue,  and  is  lined  externally  with 
a  very  thin  layer  of  skin,  continuous  with  that  of  the  meatus, 
while  internally  it  is  lined  with  mucous  membrane,  which  is 
continuous  with  that  lining  the  middle  ear,  and  which  is 
derived  from  that  of  the  pharynx  through  the  Eustachian 
tube.  A  little  below  its  centre  it  presents  a  depression,  or 
umbo,  corresponding  to  the  attachment  of  the  handle  of  the 
malleus.  As  the  CHORDA  TYMPANI  NERVE,  with  the  vessels 


THE  EAR  45 

and  nerves  supplying  the  membrane,  runs  across  above  the 
level  c#  the  umbo,  it  is  well  when  incising  the  membrane  to 
do  so  below  the  umbo.  The  chorda  tympani  is  a  branch  of  the 
facial  in  the  lower  part  of  the  aqueduct  of  Fallopius.  It  enters 
the  middle  ear  through  the  iter  chordae  posterius,  leaves  it 
through  the  iter  chordae  anterius,  and  then  joins  the  lingual 
of  the  fifth  beneath  the  external  pterygoid  muscle,  whence  it 
supplies  the  anterior  two-thirds  of  the  tongue  with  taste. 
It  communicates  in  its  course  with  the  submaxillary  and  otic 
ganglia  (see  plate).  The  gap  in  the  ring  of  bone  to  which  the 
membrane  is  attached  is  situated  above  and  anteriorly,  and 
is  called  the  NOTCH  OF  RIVINI.  From  either  extremity  of 
this  notch  a  fold  of  fibrous  tissue  extends  to  the  short  process 
of  the  malleus,  and  the  angle  so  formed  is  filled  in  with  loose 
connective  tissue,  known  as  SHRAPNELL'S  MEMBRANE,  or  the 
membrana  flaccida.  Pus  may  occasionally  force  its  way 
through  this  membrane  without  rupturing  the  membrana 
tympani.  The  membrana  tympani  may  be  ruptured  by  blows 
on  the  ear,  and  even  by  loud  noises,  while  it  is  frequently 
destroyed  by  middle-ear  disease. 

The  middle  ear,  or  tympanum,  is  a  small  cavity  which  con- 
tains the  ossicles  and  communicates  anteriorly  with  the 
pharynx  through  the  Eustachian  tube,  and  posteriorly  with 
the  mastoid  antrum  and  cells  through  the  iter.  The  lining 
membrane  of  all  these  parts,  including  the  mastoid  antrum 
and  cells,  is  continuous  with  the  pharyngeal  mucous  mem- 
brane. This  membrane  is  very  thin,  and  in  the  middle  ear 
is  thrown  into  folds  which  invest  the  ossicles,  forming  prac- 
tically ligaments  for  them,  and  also  numerous  pouches,  that 
between  the  membrana  flaccida  and  neck  of  malleus  being 
called  the  pouch  of  Prussak.  The  outer  wall  of  the  tympanum 
is  formed  by  the  tympanic  membrane,  and,  above  the  mem- 
brane, by  the  squamous  bone.  The  portion  of  the  tympanum 
above  the  level  of  the  membrana  is  called  the  ATTIC,  or  epi- 
tympanic  recess.  It  lodges  the  head  of  the  malleus,  and 
body  and  short  process  of  the  incus,  the  latter  projecting  into 
the  iter  (or  aditus  to  the  antrum),  through  which  the  attic 
of  the  tympanum  communicates  with  the  mastoid  antrum. 
Thus  the  greater  portion  of  the  ossicles  lies  above  the  level  of 
the  tympanic  membrane.  The  inner  wall  is  formed  by  the 
external  surface  of  the  internal  ear.  At  its  upper  and  posterior 


46  SURGICAL  ANATOMY 

part,  close  to  the  roof,  is  seen  the  projecting  FACIAL  CANAL. 
Below  this  is  the  FENESTRA  OVALIS,  occupied  by  the  stapes. 
Still  further  down,  but  more  anteriorly,  is  seen  the  PROMON- 
TORY or  projection  of  the  cochlea,  while  yet  further  down  and 
nearly  under  the  fenestra  ovalis  is  the  FENESTRA  ROTUNDA, 


FIG.  6.— SAGITTAL  HEAD  SECTION  PASSING  THROUGH  THE  TYMPANIC 
MEMBRANE  AND  DISPLAYING  THE  MIDDLE  EAR,  ATTIC,  ITER,  AND 
MASTOID  ANTRUM. 

The  membrane  is  shown  cut  obliquely  and  exposing  the  middle  ear,  in  which  are  seen  the 
ossicles  and  the  chorda  tympani  nerve  (white).  Below  and  behind  these  the  facial  nerve 
(white)  is  seen  in  section. 

Note  how  the  middle  ear  and  mastoid  cells  are  surrounded  by  the  condyle  of  the  jaw  in 
front,  ternporo-sphenoidal  lobe  above,  ceiebellum  behind,  and  sigmoid  sinus  below  and 
behind.  The  jugular  bulb  and  vein  are  shown  in  longitudinal  sections  (black),  and  the  inferior 
dental  nerve  (white)  in  oblique  section  within  the  lower  jaw. 

closed  by  a  thin  membrane  and  leading  to  the  scala  tympani. 
The  roof,  or  TEGMEN  TYMPANI,  situated  above  the  upper  limit 
of  the  tympanic  membrane,  is  a  very  thin  plate  of  bone,  which 
separates  the  middle  ear  from  the  dura  of  the  middle  fossa. 
In  the  infant  a  gap  exists  in  this  roof  externally,  due  to  the 
PETRO-SQUAMOSAL  SUTURE,  which  gives  passage  to  some  veins, 


THE  EAR  47 

and  traces  oi  it  may  be  found  in  the  adult.  Thus  extension 
upward^  of  pyogenic  mischief  to  the  brain  from  the  middle 
ear  may  very  readily  occur.  The  floor  below  the  lower  limit 
of  the  tympanic  membrane  and  of  the  Eustachian  tube  is 
narrower  than  the  roof  and  much  thicker.  It  separates  the 
middle  ear  from  the  dome  of  the  internal  jugular  vein.  The 
anterior  extremity  of  the  middle  ear  is  tapered  and  is  occupied 
above  by  the  canal  of  the  tensor  tympani  muscle  and  below  by 
the  Eustachian  tube,  separated  from  one  another  by  the  pro- 
cessus  cochleariformis.  This  processus  is  prolonged  back- 
wards almost  to  the  fenestra  ovalis,  where  it  forms  a  pulley 
for  the  tendon  of  the  tensor  tympani,  which  curves  round  it  to 
be  inserted  into  the  neck  of  the  malleus.  Below  the  Eustachian 
tube  is  a  thin  plate  of  bone  separating  the  middle  ear  from  the 
carotid  artery.  The  posterior  wall  presents  superiorly  the 
iter  or  communication  with  the  mastoid  antrum,  which  is 
generally  of  sufficient  size  to  admit  a  director.  Below  the 
entrance  to  the  iter  is  the  PYRAMID,  with  a  small  aperture  at 
its  summit  for  the  tendon  of  the  stapedius  muscle,  while 
external  to  the  pyramid  and  close  to  the  tympanic  membrane 
is  the  small  aperture  for  the  chorda  tympani  nerve.  The 
tympanum  is  supplied  by  the  tympanic  branch  of  the  internal 
maxillary  artery,  which  enters  through  the  Glaserian  fissure, 
the  stylo  -  mastoid  branch  of  the  posterior  auricular,  the 
petrosal  branch  of  the  middle  meningeal,  and  small  branches 
from  the  internal  carotid.  The  veins  run  upwards  to  join  the 
superior  petrosal  sinus,  downwards  to  join  the  temporo- 
maxillary  vein  and  jugular  bulb,  and  backwards  to  the  lateral 
sinus.  The  tympanic  nerve  plexus  is  formed  by  the  small 
superficial  petrosal  (from  otic  ganglion  to  facial  nerve),  small 
deep  petrosal  (from  sympathetic  surrounding  internal  carotid 
artery),  and  tympanic  branch  of  glosso-pharyngeal  (Jacob- 
son's). 

The  Eustachian  tube,  about  ij  inches  long,  and  lined  with 
ciliated  epithelium  directing  secretion  toward  the  pharynx, 
commences  at  the  anterior  extremity  of  the  middle  ear,  below 
and  to  the  inside  of  the  canal  of  the  tensor  tympani,  and  is 
directed  forwards,  inwards,  and  slightly  downwards.  For 
the  first.  |  inch  of  its  course  it  is  surrounded  by  an  osseous  wall, 
the  internal  carotid  artery  lying  to  its  inside.  It  is  narrowest 
at  the  junction  of  osseous  and  cartilaginous  portions  (isthmus), 


48  SURGICAL  ANATOMY 

and  then  expands,  presenting  a  trumpet- shaped  mouth  in  the 
pharynx,  situated  above  the  soft  palate  behind  the  inferior 
turbinate  bone.  This  mouth  is  generally  closed,  but  is  opened 
during  swallowing  by  the  action  chiefly  of  the  tensor  palati.  This 
fact  is  taken  advantage  of  in  Politzer's  method  of  inflation, 
in  which  air  is  forced  up  the  nostril  through  a  nozzle,  while 
the  patient  swallows  a  mouthful  of  water  previously  taken, 
the  mouth  and  nostrils  being  kept  firmly  closed  meanwhile. 
Probably,  however,  the  Eustachian  tubes  are  never  firmly 
closed,  as  air  can  also  be  forced  into  them  by  attempting  to 
blow  through  the  nose  while  holding  the  nostrils  ;  this  is  known 
as  Valsalva's  method  of  inflation.  These  inflations  are  per- 
formed with  a  view  to  clearing  the  Eustachian  tube,  as  when 
the  tube  is  blocked  partial  deafness  occurs.  They  are  not 
entirely  devoid  of  danger,  as,  if  septic  material  be  lodged  in 
the  tube,  it  may  be  forced  up  by  inflation  to  the  middle  ear, 
and  possibly  even  to  the  mastoid  cells,  as  the  Eustachian  tube 
and  the  iter  are  in  line  with  one  another,  the  junction  of  the 
incus  and  stapes,  however,  intervening. 

The  iter,  or  aditus,  about  J  inch  long,  leads  from  the  posterior 
extremity  of  the  attic  of  the  middle  ear  to  the  mastoid  antrum. 
Its  roof,  like  that  of  the  middle  ear,  is  composed  of  a  thin 
plate  of  bone,  separating  it  from  the  dura  of  the  temporo- 
sphenoidal  lobe.  Its  floor  and  part  of  its  inner  wall  are  formed 
of  hard  compact  bone  encasing  the  FACIAL  NERVE,  while  the 
bone  encasing  the  EXTERNAL  SEMICIRCULAR  CANAL  causes  a 
slight  prominence  on  the  inner  wall  posterior  to  the  facial 
canal. 

The  mastoid  antrum,  situated  at  the  upper  anterior  angle 
of  the  mastoid  bone  and  present  from  birth,  is  very  constant 
in  its  position,  but  varies  greatly  in  size  (sometimes  occupying 
nearly  the  whole  mastoid  process),  and  also  in  its  depth  from 
the  surface.  Like  the  middle  ear  and  iter,  it  is  lined  with  a 
thin  layer  of  mucous  membrane,  continued  through  the 
Eustachian  tube  from  the  pharynx,  and  it  is  separated  from 
the  temporo-sphenoidal  dura  by  only  a  very  thin  layer  of  bone, 
the  TEGMEN  ANTRI.  Anterior  to  the  mastoid  antrum  lies 
the  descending  portion  of  the  FACIAL  NERVE,  enclosed,  as  it 
is  in  other  parts,  by  dense  bone.  The  mastoid  antrum  is  in 
direct  communication,  by  numerous  small  canals,  with  the 
MASTOID  CELLS,  with  which  the  mastoid  process  is  honey- 


THE  EAR  49 

combed. ,  These  mastoid  cells  freely  intercommunicate  by 
similar  canals,  and  they  also  are  lined  by  mucous  membrane 
continuous  with  that  of  the  pharynx.  It  will  thus  be  seen  that 
if  ORGANISMS  gain  access  to  the  Eustachian  tube,  they  may 


FIG.   7. — HORIZONTAL   HEAD   SECTION,   PASSING   THROUGH  THE   MIDDLE 
EAR:      (VIEWED  FROM  BELOW.) 

Anteriorly  are  the  orbital  cavities  occupied  by  the  eyes,  ocular  muscles,  nerves,  fat,  etc., 
and  the  ethmoidal  and  sphenoidal  cells.  The  lower  and  anterior  extremities  of  the  temporo- 
sphenoidal  lobes  of  the  brain  are  seen,  related  anteriorly  to  the  posterior  ethmoidal  and 
sphenoidal  sinuses  and  orbits,  and  posteriorly  (on  the  left)  to  the  mastoid  cells.  On  the  right 
the  tip  of  the  condyle  of  the  jaw  is  seen  in  section,  just  external  to  the  temporo-sphenoidal  lobe, 
and  in  front  of  the  tympanic  membrane,  which  is  also  cut  across  and  separates  the  external 
from  the  middle  ear.  In  the  middle  ear  are  portions  of  the  ossicle*,  and  still  more  internally 
is  a  turn  of  the  cochlea  cut  across,  while  behind  the  middle  ear  the  facial  nerve  (white)  is  cut 
transversely.  The  trastoid  cells  and  their  relationship  to  the  sigmoid  sinus  are  well  shown,  as 
is  likewise  the  cerebellum,  presenting  a  portion  of  the  fourth  ventricle. 

travel  up  to  the  middle  ear,  iter,  mastoid  antrum,  and  mastoid 
cells,  and  as  these  structures,  and  particularly  the  latter,  are 
in  close  proximity  to  numerous  important  parts,  and  pus 
cannot  readily  find  an  exit  from  them,  life  may  readily  be 

4 


50  SURGICAL  ANATOMY 

threatened.  The  mastoid  antrum,  when  large,  or  in  other 
cases  the  mastoid  cells,  generally  projects  backwards,  beneath 
the  KNEE  OF  THE  SIGMOID  SINUS.  The  position  of  the  knee 
of  the  sinus  is  unfortunately  very  variable,  being  sometimes 
within  |  inch  of  the  posterior  osseous  wall  of  the  external 
auditory  meatus,  and  at  others  fully  i  inch  behind  it,  while 
it  also  varies  much  as  to  depth  from  the  surface.  When  the 


FIG.  7A.  —  HORIZONTAL  HEAD  SECTION,  ABOUT  £  INCH  BELOW  7. 


Note  the  seventh  and  eighth  nerves  entering  the  internal  ear  together  and  then  diverging. 
On  the  left  the  cochlea,  the  vestibule,  the  middle  ear,  her.  and  mastoid  antrum  are  shown, 
as  likewise  the  external  semicircular  canal  (black,  to  the  inside  of  the  antrum),  and  the 
sigmoid  sinus. 

mastoid  antrum  projects  far  back  behind  the  sigmoid  sinus, 
it  comes  into  relationship  with  the  dura  of  the  CEREBELLUM, 
from  which  it  may  be  separated  by  only  a  thin  layer  of  bone. 
EXTENSION  OF  SEPTIC  MATTER  UPWARDS  from  the  middle 
ear,  iter,  and  mastoid  antrum,  will  involve  the  cerebral  dura 
covering  the  temporo-sphenoidal  lobe,  and  give  rise  most 
probably  to  EXTRADURAL,  or,  if  the  dura  be  penetrated,  to 


THE  EAR  51 

INTRACEREBRAL  ABSCESS.  The  reason  why  such  extension 
does  not*  cause  generalized  meningitis  is  to  be  found  in  the 
resisting  qualities  of  the  dura  mater.  At  first  toxins  alone 
penetrate  the  dura,  and  these  set  up  an  inflammation  which  is 
local  and  leads  to  soldering  of  dura,  pia-arachnoid,  and  even 
brain  surface.  Thus,  when  organisms  do  ultimately  perforate 
the  dura,  they  are  in  a  space  confined  by  adhesions,  and  are 
not  in  the  free  subdural  space.  Small  veins  may  also  carry 
the  infection  to  the  superior  petrosal  sinus,  causing  throm- 
bosis. It  will  be  remembered  that,  owing  to  the  shape  of 
the  middle  fossa,  the  pressure  of  temporo-sphenoidal  abscesses 
is  directed  inwards,  as  evidenced  by  PRESSURE  ON  THE  THIRD 
NERVE,  causing  first  (during  the  period  of  irritation)  a  contrac- 
tion, and  later  (from  paralysis)  a  dilatation  of  the  pupil  on 
the  same  side,  and  upwards  to  the  FACE  CENTRE,  giving  rise 
to  a  paralysis  of  the  face  on  the  opposite  side,  the  mimetic 
play  of  the  features  being  retained. 

EXTENSION  BACKWARDS  from  the  mastoid  antrum  and 
cells  will  involve,  first,  the  SIGMOID  SINUS,  giving  rise  to 
sinus  thrombosis,  and  second,  possibly  the  CEREBELLUM, 
giving  rise  to  cerebellar  abscess.  Sigmoid  sinus  thrombosis 
will  extend  down  into  the  internal  jugular  in  the  neck, 
and  as  the  clot  becomes  purulent  and  broken  down  by 
the  action  of  the  organisms,  septic  emboli  may  be  swept 
to  the  lungs  (pneumonic  type),  abdomen  (typhoid  type), 
or  back  to  the  meninges  (meningeal  type).  As  the  sig- 
moid  sinus  is  formed  by  a  splitting  of  the  dura  mater, 
the  explanation  given  above  as  to  the  resisting  qualities 
of  the  dura  again  holds  as  the  reason  why  organisms  do  not 
immediately  penetrate  the  sinus  and  enter  the  circulation. 
Only  toxins  penetrate  at  first.  These  cause  the  formation  of 
a  thrombus  in  which  there  are  no  organisms,  and  when, 
ultimately,  organisms  do  enter  the  sinus,  they  encounter  a 
solid  mass  of  clot  and  not  circulating  blood.  Hence  it  is 
not  until  purulent  disintegration  of  the  clot  has  occurred  that 
systemic  infection  takes  place.  EXTENSION  INWARDS  from 
the  middle  ear  to  the  internal  ear  :  Here  the  organisms  may 
invade,  and  then  travel  along  the^sheaths  of  the  SEVENTH 
AND  EIGHTH  NERVES,  and  so  reach  ^the  surface  of  the  brain 
and  give  rise  to  generalized  meningitis.  The  FACIAL  NERVE 
may  be  destroyed  without  invasion  of  the  cerebral  membranes, 

4—2 


52  SURGICAL  ANATOMY 

causing  complete  paralysis  of  the  face  oji  the  same  side 
(contrast  with  effect  of  pressure  on  face  centre  given  above). 

It  is  thus  a  matter  of  great  importance  to  be  able  to  go 
down  upon  the  mastoid  antrum,  and  give  exit  to  the  pus 
contained  within  it,  without  damaging  the  very  important 
structures  lying  upon  all  sides  of  it.  This,  fortunately,  is 
a  comparatively  easy  matter  owing  to  the  constant  relation- 
ship between  the  mastoid  antrum  and  the  surface  markings 
to  be  described.  The  posterior  root  of  the  zygoma  passes 
nearly  horizontally  across  the  superior  border  of  the  external 
auditory  osseous  meatus,  and  extends  backwards  beyond  it, 
forming  an  angle  with  the  posterior  wall  of  the  osseous  meatus. 
This  angle  can  always  be  made  out  on  the  surface  of  the  bone, 
and  is  frequently  occupied  by  a  very  well-marked  depression 
in  the  bone.  The  angle  may  be  converted  into  a  triangle  by 
supplying  an  imaginary  third  or  posterior  side,  formed  by 
drawing  a  tangent  upwards  from  the  posterior  part  of  the 
osseous  auditory  meatus,  and  is  called  the  suprameatal  triangle 
(Macewen) . 

An  aperture  made  straight  in  through  this  triangle, -keeping 
at  right  angles  with  the  surface  of  the  bone,  will  strike  the 
antrum,  without  damaging  the  sigmoid  sinus,  provided  that 
the  aperture  made  be  not  large.  The  spine  of  Henle  some- 
times given  as  a  guide  to  the  antrum,  is  generally  only  present 
in  well-marked  skulls,  in  which  the  suprameatal  triangle  is 
indicated  by  a  distinct  depression  in  the  bone.  When  present, 
the  spine  is  situated  on  the  margin  of  the  posterior  wall  of 
the  osseous  meatus.  Such  an  aperture  would  enable  pus 
to  escape,  but  would  not,  as  a  rule,  cure  the  condition,  a 
RADICAL  MASTOIDECTOMY  performed  with  proper  instruments 
being  necessary  for  this  purpose.  In  performing  the  radical 
operation  much  care  is  required.  When  working  backwards 
the  sigmoid  sinus  may  be  exposed  at  any  moment,  and  as 
its  position  cannot  be  determined  by  landmarks,  the  operation 
can  only  be  safely  performed  by  an  instrument  which  will 
cut  away  the  diseased  bone  gradually  without  damaging  the 
soft  parts  (such  an  instrument  is  the  surgical  bur,  when 
properly  made).  In  the  radical  operation  also  it  is  usual  to 
lay  the  middle  ear  and  mastoid  antrum  into  one,  by  cutting 
away  the  bridge  of  bone  which,  forming  the  external  wall  of 
the  iter,  separates  the  two.  Here  again  care  must  be  exercised, 


THE  EAR  53 

as  if  the  bone  on  the  inner  side  of  the  iter  be  cut,  both  the 
facial  nerve  and  the  external  semicircular  canal  may  be 
damaged.  When  operating  with  a  surgical  bur,  the  FACIAL 
CANAL,  even  in  very  extensive  dissections,  can  be  recognized 
and  avoided,  owing  to  its  being  encased  in  dense  bone,  which 
contrasts  with  the  softer  bone  surrounding  it.  The  FACIAL 
NERVE  enters  the  internal  auditory  meatus  along  with  the 
eighth  nerve,  and  at  the  bottom  of  the  internal  meatus  enters 
the  AQUEDUCT  OF  FALLOPius,  the  canal  of  dense  bone  already 
mentioned.  In  this  it  first  runs  outwards  and  forwards  until 
it  reaches  the  inner  wall  of  the  tympanum,  when  it  suddenly 
bends  backwards  and  downwards  first  to  the  inner  side  and 
then  to  the  floor  of  the  iter.  Finally,  it  descends  almost 
vertically  just  in  front  of  and  on  the  deep  surface  of  the 
antrum,  to  the  stylo-mastoid  foramen.  The  OSSICLES  are 
frequently  involved  in  disease,  and  are  generally  removed  in 
a  radical  operation,  with  the  exception  of  the  stapes,  which 
is  fixed  in  the  foramen  ovale.  It  is  worthy  of  note  that 
hearing  is  often  much  improved  after  the  radical  operation, 
partly  due,  no  doubt,  to  the  removal  of  the  granulation  masses, 
which  previously  blocked  up  the  parts,  and  also  possibly  to 
the  freeing  of  the  stapes. 

The  mastoid  process  varies  much  in  structure.  Sometimes, 
and  especially  after  long-standing  disease,  it  is  hard  and  dense, 
and  contains  few  cells.  At  others  it  is  honeycombed  with 
intercommunicating  cells,  one  of  which  may  open  at  the  tip, 
forming  a  '  Bezold's  aperture.'  Where  mastoiditis  occurs 
in  such  cases,  the  pus  may  escape  by  this  aperture  and  present 
in  the  neck,  generally  behind  the  sterno-mastoid.  In  most 
cases  the  pus,  when  if  escapes,  does  so  by  the  Eustachian  tube, 
or,  once  perforation  of  the  drum  has  occurred,  by  the  external 
ear.  It  is  important  to  remember,  however,  that  active 
mischief  may  be  going  on,  although  the  drum  is  intact.  Some- 
times the  pus  finds  its  way  to  the  surface  of  the  mastoid  bone, 
under  the  periosteum,  by  a  process  of  caries,  or  through 
remains  of  the  masto-squamosal  suture,  and  in  such  cases 
the  periosteum,  carrying  with  it  the  pinna,  is  raised  from  the 
bone,  so  that  the  patient  presents  the  appearance  of  having 
a  very  prominent  ear,  which  also  is  projected  forwards. 
A  simple  incision  into  this  superficial  abscess  is  known  to 
aurists  as  Wilde's  incision.  It  cannot,  of  course,  cure  the 


54  SURGICAL  ANATOMY 

condition.  In  some  cases,  where  such  an  aperture  exists  on 
the  surface  of  the  mastoid,  the  patient  may  possess  the  power 
of  inflating  the  superficial  tissues  by  forcing  air  through  the 
Eustachian  tube.  Such  tumours  are  known  as  pneumato- 
celes.  Apart  from  disease  due  to  pathogenic  organisms,  the 
mastoid  antrum  is  sometimes  occupied  by  an  epithelial  tumour, 
composed  of  pearly  masses  of  epithelium  (CHOLESTEATOMA). 

In  such  cases  the  antrum  is  generally  very  large,  extending 
deeply  beneath  the  sigmoid  sinus,  and  profuse  suppuration 
appears  to  occur  readily  on  the  invasion  of  organisms,  and  is, 
of  course,  extensive.  Sometimes  pathogenic  processes  extend 
inwards  and  affect  the  internal  ear.  In  some  of  these  the  semi- 
circular canals  may  be  slowly  affected  (MENIKRE'S  DISEASE), 
and  even  the  whole  osseous  labyrinth,  consisting  of  cochlea, 
vestibule,  and  canals,  has  been  found  lying  detached  in  the 
ear  as  the  result  of  suph  processes. 

THE  EYE  AND  OCULAR  APPARATUS. 

The  Ocular  Apparatus. — The  eyeball,  lying  in  the  orbital 
cavity,  is  largely  protected  from  injury  by  the  prominent  eye- 
brow and  the  bones  forming  the  cavity.  The  EYEBROW  possesses 
a  considerable  range  of  movement,  and  when  struck  is  fre- 
quently divided  by  the  underlying  bone  from  within  outwards, 
a  clean-cut  wound  being  thus  produced.  The  well-defined 
supra-orbital  margin  is  easily  made  out  by  palpation,  as  well 
as  the  supra-orbital  notch  at  the  junction  of  its  inner  and 
middle  thirds,  which  transmits  the  supra-orbital  vessels  and 
nerve.  Penetrating  wounds  in  the  orbital  region  are  fre- 
quently serious,  as  the  bones  in  this  region  being  very  thin, 
the  brain,  cavernous  sinus,  or  even  the  internal  carotid  artery, 
may  be  damaged.  Arterio-venom  aneurysm  may  follow  the 
wounding  of  the  two  latter  structures.  The  UPPER  EYELID 
covers  about  three-quarters  of  the  anterior  surface  of  the 
eyeball,  and  opening  and  closing  of  the  eye  is  chiefly  due  to 
its  movements.  The  tar  sal  cartilage  of  the  upper  eyelid  is 
the  larger  of  the  two,  and,  commencing  close  to  the  palpebral 
fissure,  extends  upwards  for  rather  more  than  J  inch.  Beyond 
its  stiff  upper  margin  the  eyelid  is  soft,  and  this  fact  is  illus- 
trated in  the  usual  method  of  everting  the  eyelid.  On 
eversion  of  the  lids  the  large  Meibomian  glands,  whose  ducts 


THE  EYE  55 

open  along  their  margins,  may  be  seen  showing  through  the 
conjunctiva.  Tarsal  cysts  are  produced  by  blocking  of  these 
ducts,  while  a  stye,  or  hordeolum,  is  a  small  boil  originating 
in  a  hair  follicle  or  sebaceous  gland.  Marginal  blepharitis 
is  an  extensive  inflammation  of  the  palpebral  margin,  which 
frequently  results  in  an  inturning  of  hair  follicles,  the  lashes 
thus  growing  toward  and  touching  the  conjunctiva,  causing 
what  is  known  as  trichiasis.  The  skin  of  the  eyelids  is  very 
lax,  and  advantage  is  taken  of  this  in  performing  numerous 
plastic  operations  on  the  lids.  This  laxity,  however,  also 
favours  the  occurrence  of  marked  deformity  by  traction  of 
tubercular  and  other  cicatrices,  giving  rise  frequently  to  an 
eversion  of  the  lower  lid,  known  as  ectropion.  Entropion, 
or  incurling  of  the  lid,  is  generally  the  result  of  prolonged 
conjunctivitis,  and  most  frequently  affects  the  upper  lid. 
Rodent  ulcer  frequently  affects  the  eyelid,  where  the  fact  that 
it  does  not  cause  contraction  is  well  illustrated,  no  contraction 
deformity  resulting  from  its  presence.  The  laxness  of  the 
tissues  of  the  eyelids  is  also  illustrated  by  the  frequent  occur- 
rence of  oedema  from  inflammatory  conditions  and  Bright 's 
disease  ;  by  occasional  emphysema  in  fracture  of  the  nasal 
bone,  with  tearing  of  the  nasal  mucous  membrane  ;  and  by  the 
readiness  with  which  effusions  of  blood  occur  into  them  from 
a  blow,  producing  a  '  BLACK  EYE.'  This  condition  requires 
to  be  distinguished  from  effusion  of  blood  resulting  from 
fracture  of  the  orbital  plate  of  the  frontal  bone.  In  black 
eye  the  effusion  into  the  eyelids  and  under  the  conjunctiva 
occurs  within  a  few  hours  of  the  injury,  is  general  and  diffuse, 
is  generally  of  a  chocolate  colour,  and  the  subconjunctival 
portion  is  limited  to  the  anterior  segment  of  the  eyeball. 
The  effusion  due  to  fracture  seldom  appears  before  some  forty- 
eight  hours  have  elapsed,  is  patchy,  of  a  blue  colour  over  the 
eyelids,  of  which  the  lower  is  generally  first  affected  (owing 
to  gravity),  and  bright  red  over  the  conjunctival  portion,  the 
effusion  here  not  being  limited  to  the  anterior  segment,  but 
extending  backwards  beyond  the  visible  portion  of  the  eyeball. 
As  the  occipito-frontalis  muscle  sends  an  expansion  into  the 
upper  eyelids,  effusions  of  pus  or  blood  may  extend  from  the 
scalp  into  the  upper  lid. 

The  eyelids  are  closed  by  the  facial  nerve  acting  on  the 
orbicularis  palpebrarum.     Thus,  in  a  complete  facial  paralysis 


56  SURGICAL  ANATOMY 

due  to  destruction  of  the  nerve  trunk  the  patient  cannot 
close  the  eye  on  the  affected  side  (lagophthalmos)  ;  the  eyeball 
appears  slightly  prominent  (proptosis],  owing  to  want  of  the 
restraining  action  of  the  orbicularis,  and  the  conjunctiva 
tends  sooner  or  later  to  become  inflamed  from  undue  exposure. 
The  lower  eyelid  tends  to  droop  outwards,  allowing  the  tears, 
the  secretion  of  which  is  increased  by  the  irritation,  to  flow 
on  to  the  cheek  (epiphora}.  Blepharospasm,  or  persistent 
contraction  of  the  muscle,  is  seen  in  photophobia  from  inflam- 
mation of  the  cornea  and  uveal  tract,  and  sometimes  in  cases 
of  otitis,  trigeminal  neuralgia,  carious  teeth,  etc.  The  eyelids 
are  opened  by  the  third  nerve  acting  on  the  levator  palpebrae 
superioris.  In  paralysis  of  the  third  nerve  there  is  therefore  a 
marked  drooping  of  the  upper  eyelid  (ptosis),  which  can  only 
be  slightly  raised  voluntarily  by  an  exaggerated  action  of 
the  frontalis  muscle,  which  at  the  same  time  wrinkles  the 
forehead.  A  slight  ptosis  of  the  upper  eyelid  may  also  be 
produced  by  paralysis  of  the  cervical  sympathetic,  which  then 
cannot  act  on  the  unstriped  fibres,  and  a  pseudo  ptosis  may 
be  caused  by  great  swelling  of  the  eyelid,  or  lipoma  of  the  skin 
fold  overhanging  the  upper  eyelid  (blephar o-chalasis] ,  or  to 
some  congenital  defect  in  the  muscles.  The  fifth  nerve  sup- 
plies sensation  to  the  eyelid,  the  first  division  supplying  four 
twigs  to  the  upper,  and  the  infra- orbital  of  the  second  division 
supplying  the  lower.  The  blood-supply  is  derived  from  the 
ophthalmic  of  the  internal  carotid,  which  sends  a  small 
twig  to  the  inner  side  of  each  eyelid,  while  by  its  lachrymal 
branch  it  sends  a  small  twig  to  the  outer  side  of  each.  Some 
of  the  lymphatics  drain  to  the  preauricular  glands. 

While  the  eyelids  meet  externally  at  an  acute  angle  to 
form  the  outer  canthus,  internally  they  first  diverge  from  one 
another  (lacus  lachrymalis)  before  forming  the  inner  canthus. 
At  the  point  of  divergence  on  each  lid  there  is  a  slight  conical 
elevation,  with  a  small  aperture  at  its  summit,  the  punctwn 
lachrymale,  which  communicates  with  the  lachrymal  canali- 
culus,  and  conveys  the  tears  to  the  lachrymal  sac.  The  small 
space  left  by  the  divergence  of  the  lids  or  lacus  lachrymalis 
is  occupied  by  the  lachrymal  caruncle.  The  tarsal  cartilages 
of  the  upper  and  lower  eyelids  are  connected  internally  and 
externally  by  the  tarsal  ligaments,  which  are  Y-shaped,  the 
stem  of  the  Y  being  attached  to  the  malar  bone  externally, 


THE  EYE  57 

and  to  the  superior  maxilla  in  the  case  of  the  internal  ligament, 
while  thfe  limbs  are  attached  to  the  upper  and  lower  tarsal 
plates.  The  internal  tarsal  ligament,  or  tendo  oculi,  is  the 
stronger,  and  passes  to  its  insertion  in  front  of  the  lachrymal 
sac,  while  it  may  send  a  posterior  limb  round  the  lachrymal 
sac  to  be  inserted  into  the  lachrymal  bone.  The  SEPTUM 
ORBITALE,  which  forms  a  diaphragm  separating  the  superficial 
from  the  deep  structures  of  the  orbit,  is  a  membranous 
expansion  from  the  periosteum  of  the  margin  of  the  orbit  into 
the  eyelids.  In  the  upper  eyelid  it  blends  with  the  tendon 
of  the  levator  palpebrae  superioris,  and  in  the  lower  with  the 
tarsal  cartilage.  Externally  it  forms  the  external  tarsal 
ligament,  while  internally  it  diverges  from  the  internal  tarsal 
ligament,  and  passes  behind  the  lachrymal  sac  to  be  inserted 
into  the  lachrymal  bone. 

Congenital  defects  of  the  eyelids  are  uncommon.  Epican- 
thus  is  the  term  applied  to  a  semilunar  fold  of  skin  extending 
over  the  inner  canthus  from  the  upper  to  the  lower  eyelid  ; 
ankylo-blepharon  is  a  fusion  of  the  two  eyelids  ;  colobomz, 
a  vertical  fissure,  sometimes  associated  with  a  corneal  der- 
moid.  Chalazion  is  a  granulomatous  tumour  which  occurs 
in  the  substance  of  the  eyelid,  generally  the  upper. 

The  CONJUNCTIVA  is  a  delicate  mucous  membrane,  covered 
with  epithelium,  which  lines  the  inner  surfaces  of  the  eyelids 
and  the  front  of  the  globe.  The  reflections  from  the  eyelids 
to  the  globe  are  called  the  superior  and  inferior  fornices. 
Only  the  epithelial  layer  covers  the  front  of  the  cornea,  the 
connective  tissue  layers  ceasing  at  the  corneal  margin.  The 
caruncle  at  the  inner  canthus  is  formed  from  conjunctiva,  and 
just  external  to  the  caruncle  is  the  plica  semilunaris,  a  fold 
of  the  membrane  which  disappears  on  full  external  rotation 
of  the  eyeball,  to  permit  of  which  movement  it  exists.  It 
corresponds  to  the  nictitating  membrane  of  birds.  The 
conjunctiva  is  but  loosely  attached  to  the  eyeball,  and  use  is 
made  of  this  fact  in  plastic  operations  for  the  relief  of  symble- 
pharon,  in  which,  owing  to  injury,  the  eyelids  become  adherent 
to  the  eyeball.  This  laxness  readily  permits  of  redematous 
swelling  of  the  conjunctiva  (chemosis)  occurring,  as  well  as 
of  subconjunctival  hemorrhage  from  rupture  of  the  unsupported 
vessels. 

The  lachrymal  and  two  palpebral  branches  of  the  ophthal- 


58  SURGICAL  ANATOMY 

mic  branch  of  the  internal  carotid  supply  the  conjunctiva 
with  blood,  while  it  is  supplied  by  four  nerves  :  above,  the 
supratrochlear  ;  outside,  the  lachrymal  ;  inside,  the  infra- 
trochlear  (all  derived  from  the  ophthalmic  division  of  the 
fifth)  ;  and  below,  by  the  palpebral  branches  of  the  superior 
maxillary  of  the  fifth. 

The  conjunctiva  is  subject  to  both  acute  and  chronic  in- 
flammation. In  the  acute  form  the  conjunctiva  becomes  deeply 
congested,  the  congestion  generally  being  arrested  at  the 
corneal  margin,  where  the  normal  conjunctival  vessels  ter- 
minate. In  iritis  a  zone  of  circumcorneal  inflammation  is 
also  seen,  but  the  individual  vessels  cannot  be  distinguished  ; 
whereas  in  conjunctivitis  they  are  not  only  readily  distin- 
guishable, but  can  be  moved  with  the  conjunctiva  on  the 
cornea  by  manipulation  of  the  lower  eyelid. 

Trachoma,  or  chronic  granular  conjunctivitis,  is  most  often 
met  with  among  the  poor,  and  frequently  gives  rise  to  entro- 
pion.  Pterygium  is  a  triangular  vascularized  thickening  of 
conjunctiva,  occurring  most  frequently  to  the  inner  side  of 
the  cornea,  upon  which  its  apex  abuts  and  over  which  it  may 
grow. 

The  LACHRYMAL  GLAND,  which,  occupying  the  fovea  lachry- 
malis  of  the  frontal  bone,  lies  at  the  upper  and  outer  part  of 
the  orbit  behind  the  conjunctiva,  secretes  the  tears  which 
serve  to  keep  the  conjunctiva  moist,  and  to  remove  small 
particles  which  may  have  settled  on  the  surface.  The  gland 
consists  of  two  lobes,  separated  by  a  process  of  Tenon's  capsule. 
The  orbital  lobe  is  the  larger  and  more  important  ;  the  smaller 
is  known  as  the  palpebral  portion.  Excision  of  the  gland 
may  be  performed  for  tumour  or  intractable  epiphora  (over- 
flow of  tears  on  to  the  cheek),  sufficient  moisture  being  subse- 
quently secreted  by  small  detached  lobules.  The  gland  is 
supplied  by  the  lachrymal  of  the  fifth,  stimulation  of  which, 
either  directly  or  reflexly  through  particularly  the  nasal 
branches,  causes  profuse  lachrymation. 

The  tears  are  conveyed  from  the  gland  to  the  surface  of 
the  conjunctiva  by  numerous  small  ducts  which  pierce  the 
conjunctiva  at  its  reflection  on  to  the  upper  eyelid.  From 
thence  they  are  carried  across  the  front  of  the  eyeball  by 
gravity,  capillarity,  and  the  frequent  blinking  action  of  the 
eyelids,  to  the  inner  angle,  where,  save  when  the  secretion 


THE  EYE  59 

is  excessive,  they  enter  the  lachrymal  canaliculi  through  the 
lachrymal  puncta  on  the  eyelids.  The  canaliculi,  about  J  inch 
long,  run  first  vertically,  the  upper  upwards  and  the  lower 
downwards,  then  horizontally  inwards  and  finally  open  close 
together  or  by  a  single  opening  into  the  lachrymal  sac. 
The  lachrymal  sac  occupies  the  lachrymal  groove,  lying  upon 
the  orbital  septum  (which  is  attached  to  the  crest  of  the 
lachrymal  bone),  the  lachrymal  bone,  and  a  portion  of  the 
nasal  process  of  the  superior  maxilla,  while  in  front  it  is  crossed 
above  by  the  tendo  oculi,  but  below  is  comparatively  super- 
ficial, lying  under  the  skin  and  orbicularis  muscle.  Its 
junction  with  the  lachrymal  canal  is  the  narrowest  portion 
of  the  common  apparatus.  The  nasal  duct  continues  from 
the  sac  through  an  osseous  canal,  the  lachrymal  canal,  formed 
by  the  lachrymal  and  ascending  process  of  the  superior  maxilla 
above  and  the  inferior  turbinate  and  superior  maxilla  below, 
to  open  by  a  small  aperture  in  the  mucous  membrane  of  the 
inferior  meatus  of  the  nose.  Its  direction  downwards  and 
backwards  is  indicated  by  a  line  from  the  commencement 
of  the  lachrymal  canal  to  the  first  upper  molar.  The  lachry- 
mal passages  are  liable  to  inflammatory  infection  from  the 
conjunctiva  and  the  nose,  which  parts  may  infect  one  another 
through  this  channel.  Inflammation  and  injury  of  the  duct 
tend  to  cause  blocking  and  consequent  overflow  of  tears 
(epiphora).  Sometimes  also  the  lachrymal  sac  becomes 
inflamed  and  distended  (dacryocystitis),  which  may  even  go 
on  to  suppuration,  the  abscess  pointing  below  the  tendo 
oculi. 

The  ocular  muscles,  with  the  exception  of  the  inferior 
oblique,  take  origin -from  a  common  tendon,  which  nearly 
surrounds  the  optic  foramen.  The  inferior  oblique  arises 
from  the  antero-nasal  aspect  of  the  orbital  floor,  and 
then,  passing  backwards  and  outwards  under  the  rectus 
inferior,  turns  up  between  the  rectus  externus  and  the  eye- 
ball, to  be  inserted  into  the  posterior  temporal  aspect  of  the 
eyeball.  The  superior  oblique  passes  forwards  between  the 
recti  superior  and  internus  to  the  inner  side  of  the  anterior 
margin  of  the  orbit,  where  it  passes  through  a  pulley,  and  is 
then  directed  down  and  outwards  beneath  the  tendon  of  the 
rectus  superior,  to  be  inserted  a  little  above  and  anterior  to 
the  inferior  oblique  into  the  temporal  aspect  of  the  eyeball 


6o  SURGICAL  ANATOMY 

between  the  superior  and  external  recti,  and  midway  between 
the  cornea  and  entrance  of  the  optic  nerve. 

The  internal  and  external  recti,  having  median  insertions, 
rotate  the  eye  upon  its  true  vertical  axis  inwards  and  out- 
wards respectively.  The  superior  and  inferior  recti,  being 
inserted  external  to  the  median  position,  rotate  the  eyeball 
upon  a  horizontal  axis,  which,  instead  of  being  strictly  coronal, 
is  directed  backwards  and  outwards.  When  acting  alone, 
therefore,  in  addition  to  turning  the  eyeball  up  and  down, 
they  also  turn  it  to  the  nasal  side. 

The  superior  and  inferior  oblique  muscles  rotate  the  eyeball 
round  a  horizontal  axis  which  is  likewise  not  coronal,  but  is 
inclined  forwards  and  outwards  nearly  at  right  angles  (75 
degrees)  to  the  axis  of  the  recti  muscles.  The  oblique  muscles 
accordingly  turn  the  eyeball  down  and  up,  and  at  the  same 
time  turn  it  toward  the  temporal  side.  Hence,  to  obtain  a 
movement  of  the  eyeball  directly  upwards,  the  superior  rectus 
and  inferior  oblique  act  together,  the  inward  tendency  of  the 
oblique  being  corrected  by  the  outward  tendency  of  the  rectus, 
and  similarly,  in  moving  the  eyeball  directly  downwards,  the 
inferior  rectus  and  superior  oblique  act  together. 

NERVE-SUPPLY. — All  these  muscles  are  supplied  by  the 
third  nerve,  except  the  superior  oblique,  which  is  supplied  by 
the  fourth,  and  the  external  rectus,  which  is  supplied  by  the 
sixth.  The  third  nerve  also  supplies  the  levator  palpebrae 
superioris,  and  indirectly  the  iris  and  ciliary  muscle  of  the 
eyeball,  through  the  ciliary  ganglion. 

A  complete  paralysis  of  the  third  nerve  accordingly  causes 
ptosis,  or  drooping  of  the  eyelid  ;  external  rotation  of  the  eye- 
ball, and  consequent  diplopia  ;  fixation  of  the  eyeball,  save 
for  down  and  outward  movements  ;  loss  of  power  of  accom- 
modation (ciliary  paralysis)  ;  and  dilatation  of  pupil.  An 
irritation  of  the  third  nerve  causes  contraction  of  the  pupil. 

The  fourth  nerve  is  rarely  affected  alone,  and  when  it  is, 
causes  slight  upward  movement,  with  limitation  of  downward 
movement  of  the  eyeball,  and  possibly  diplopia. 

When  the  sixth  nerve  is  paralyzed  there  is  convergent 
strabismus,  with  consequent  diplopia,  while  external  rotation 
is  very  slight,  the  obliques  only  being  capable  of  rotating  the 
eye  so  as  to  look  directly  forwards. 

The  first  or  ophthalmic  division  of  the  fifth  nerve  supplies 


THE  EYE  61 

sensation  by  its  three  branches  to  the  skin  of  the  brow,  upper 
eyelid,  r5oth  canthi,  and  nose  ;  eyeball  and  conjunctiva,  except 
that  of  the  lower  lid  ;  and  also  the  nasal  mucous  membrane. 
Lesions  of  this  branch  are  followed  by  loss  of  reflex  blinking, 
and  hence  irritation  and  ulceration  of  the  cornea  frequently 
follow. 

The  third,  fourth,  sixth,  and  first  divisions,  of  the  five  nerves 
may  be  pressed  on  and  paralyzed  by  tumours  of  the  orbit  or 
sphenoidal  fissure.  The  third  nerve  is  frequently  affected  by, 
and  gives  valuable  indications  of,  pressure  in  the  middle  fossa, 
arising  from  bleeding  from  the  middle  meningeal  artery,  or 
abscess  or  tumour  of  the  temporo-sphenoidal  region.  Slight 
pressure  upon  it  causes  irritation,  and  hence  contraction  of 
the  pupil,  whereas  great  pressure  causes  paralysis  with  dilata- 
tion of  the  pupil.  The  sixth  nerve  and  the  optic  nerve  itself 
may  be  divided  by  orbital  fractures. 

The  sympathetic  supplies  some  unstriped  fibres  in  the  upper 
eyelid,  the  unstriped  orbitalis  muscle  of  Muller  which  bridges 
the  spheno -maxillary  fissure,  and  the  radial  or  dilator  fibres 
of  the  iris.  In  paralysis  of  the  cervical  sympathetic,  there- 
fore, there  is  narrowing  of  the  palpebral  fissure,  recession  of 
the  globe,  and  contraction  of  the  pupil. 

The  BLOOD-SUPPLY  of  the  orbit  is  by  the  ophthalmic  artery 
from  the  internal  carotid,  which  pursues  a  tortuous  course 
through  the  fat  of  the  upper  segment  of  the  orbital  cavity, 
gives  off  several  branches,  including  the  central  artery  of  the 
retina,  and  terminates  by  inosculating  with  the  angular  branch 
of  the  facial.  The  blood  returns  through  the  superior  and 
inferior  ophthalmic  veins  to  the  cavernous  sinus.  As  these 
veins  communicate  with  those  of  the  face  and  nose  they  form 
a  channel  for  the  ready  extension  of  organisms  to  the  cavernous 
sinus,  resulting  in  cavernous  sinus  thrombosis.  An  arterio- 
venous  aneurysm  may  result  from  communication  between  the 
ophthalmic  artery  and  veins,  or  indirectly  between  the  artery 
and  the  sinus,  causing  dilatation  and  pulsation  of  the  veins  of 
the  eyeball  and  forehead.  Aneurysm  of  the  artery  itself  is 
sometimes  met  with,  as  are  also  pulsating  sarcomas. 

Suppurative  processes  occurring  in  the  orbital  cavity  tend  to 
spread  rapidly,  causing  proptosis,  with  redness  and  swelling 
of  the  conjunctiva  and  eyelids,  and  possibly  destruction  of  the 
eyeball,  and  by  extension  backwards  cavernous  sinus  throm- 


62  SURGICAL  ANATOMY 

bosis.  Abscesses  frequently  discharge  at  the  outer  side  of  the 
lower  eyelid,  and  this  is  generally  the  best  point  for  evacuating 
them. 

The  eyeball  is  situated  within  the  orbit,  rather  to  the  nasal 
side  of  the  centre,  and  hence,  when  excising,  it  is  generally 
most  convenient  to  introduce  the  scissors  for  division  of  the 
nerve  from  the  outer  side.  It  is  invested  by  the  capsule  of 
Tenon,  which  may  be  regarded  as  its  socket.  Commencing  in 
front  at  the  margin  of  the  cornea,  and  lying  under  the  con- 
junctiva, with  which  it  is  fused  at  this  part,  the  capsule  passes 
back  over  the  eyeball,  to  which  it  is  loosely  attached  by 
areolar  tissue,  to  the  point  of  entrance  of  the  optic  nerve,  with 
the  sheath  of  which  it  fuses.  The  capsule  is  thus  in  contact 
on  its  inner  surface  with  the  globe  of  the  eyeball,  and  on  its 
outer  with  the  orbital  fat. 

The  tendons  of  the  ocular  muscles  pierce  this  capsule 
opposite  the  equator  of  the  globe,  a  reflection  of  the  capsule 
to  form  a  sheath  being  received  by  each  of  the  recti  muscles 
as  they  do  so.  At  each  of  these  reflections  the  capsule  is 
strengthened  by  loops  of  fibrous  tissue — the  intracapsular  liga- 
ments— the  extremities  being  attached  to  the  orbital  wall, 
while  the  loops  pass  under  the  muscular  tendons,  forming 
pulleys,  upon  which  the  recti  muscles  work,  and  which  thus 
protect  the  globe  from  pressure.  The  ligaments  supplying  the 
internal  and  external  recti,  specially  well  developed  and 
attached  at  their  extremities  to  the  lachrymal  and  malar 
bones  respectively,  are  known  as  check  ligaments,  and  limit 
excessive  rotation  of  the  globe  inwards  or  outwards.  The 
most  important  attachment  of  the  capsule  to  the  orbital  wall 
is  afforded  by  the  SUSPENSORY  LIGAMENT  OF  LOCKWOOD, 
which,  attached  at  its  extremities  to  the  malar  and  lachrymal 
bones,  runs  across  under  the  anterior  part  of  the  eyeball,  and 
so  supports  it.  This  ligament  is  practically  part  of  the  cap- 
sule, becoming  intimately  fused  with  it  as  it  passes  under  the 
eyeball.  In  excising  the  upper  jaw  it  is  important  to  preserve 
this  suspensory  ligament,  otherwise  the  eyeball  tends  to  sink 
downwards.  It  also  forms  a  check  ligament  for  the  inferior 
rectus,  while  the  superior  rectus  is  checked  by  connection  with 
the  levator  palpebrae. 

The  Eyeball,  which,  but  for  the  corneal  portion,  is  spherical, 
is  composed  of  three  coats.  The  outer  consists  of  sclerotic 


THE  EYE 


FIG.  8. — DIAGRAM  OF  EYE. 
(After  Fuchs.) 


1.  Eyelid  with  lashes,  openings  of  Meibomian  17. 

glands  and  lachrymal  punctum.  18. 

2.  Cornea.  19. 

3.  Anterior  chamber.  20. 

4.  Iris,  with  posterior  chamber  behind  it.  21. 

5.  Canal  of  Schlemm.  22. 

6.  Lens.  23. 

7.  Suspensory  ligament,  containing  the  canal  24. 

of  Petit.  25. 

8.  Ciliary  process,  containing  longitudinal  and  26. 

circular    fibres    of   ciliary    muscle    and  27. 

spaces  of  Fontana.  28. 

9.  Vitreous  surrounded  by  the  hyaloid  mem-  29. 

brane.  30. 

10.  Axis.  31. 

n.   Equator.  32- 

12.  Hyaloid  canal  of  Stilling.  33. 

13.  Optic  disc.  34- 

14.  Fovea  centralis.  35. 

15.  Central  artery  of  retina. 

16.  Optic  nerve. 


Rectus  externus. 

Rectus  internus. 

Internal  check  ligament. 

External  check  ligament. 

Retina. 

Chorioid. 

Sclerotic. 

Tenon's  capsule. 

Ora  serrata. 

Orbicularis  ciliaris. 

Plica  semilunaris  of  conjunctiva. 

Caruncle. 

Lachrymal  sac. 

Nasal  process  of  upper  jaw. 

Lachrymal  bone. 

Orbital  plate  of  ethmoid. 

Inner  palpebral  ligament. 

Anterior  limb  of  palpebral  ligament. 

Posterior     limb    of    ligament    with 

Horner's     muscle    (tensor     tarn) 

springing  from  it. 


64  SURGICAL  ANATOMY 

and  cornea  ;  the  middle  of  chorioid,  ciliary  body,  and  iris  ;  and 
the  inner  of  the  retina.  Where  the  antero-posterior  diameter 
of  the  eyeball  is  normal,  the  eye  is  said  to  be  emmetropic  ; 
where  too  short,  a  condition  of  hypermetropia  is  produced  ; 
and  where  it  is  too  long,  myopia  exists.  Hypermetropia  is 
corrected  by  the  use  of  a  convex  lens,  which  brings  the  rays 
more  quickly  to  a  focus  ;  and  myopia  by  a  concave  lens,  which 
delays  the  convergence. 

Outer  Coat. — The  SCLEROTIC  is  a  dense,  unyielding,  non- 
vascular  structure,  which  does  not  readily  become  inflamed 
nor  yield  to  pressure.  This  latter  characteristic  accounts  for 
the  pain  from  pressure  on  the  nerves  experienced  in  increased 
intra-ocular  tension,  as  in  glaucoma.  The  weakest  part  of  the 
sclerotic  is  at  the  optic  disc,  which  yields  to  increased  tension, 
producing  the  glaucomatous  cup,  while,  with  a  further  increase 
of  pressure,  the  eyeball  expands  laterally  rather  than  verti- 
cally. When  rupture  of  the  globe  occurs  from  violence,  it  is 
generally  the  sclerotic  which  gives  way,  the  rent  occurring 
through  the  thinnest  part,  near  the  corneal  junction. 

The  CORNEA,  which  is  transparent,  and  convex  in  shape, 
converges  parallel  rays  of  light  upon  the  lens.  Not  infre- 
quently it  is  irregularly  curved,  the  curvature  being  generally 
greatest  in  the  vertical  meridian,  thus  giving  rise  to  astig- 
matism. Occasionally  it  has  a  conical  shape  (keratoconus}. 
The  posterior  elastic  lamina  of  the  cornea,  or  membrane  of 
Descemet,  is  of  importance,  as  it  shuts  off  the  cornea  from  the 
aqueous  humour,  and  so  preserves  its  translucency.  It  also 
prevents  the  invasion  of  leucocytes  from  the  anterior  chamber 
in  inflammatory  processes,  which  therefore  collect  in  the 
chamber,  causing  hypopyon.  It  must,  therefore,  not  be  broken 
through  in  operating  for  opacity  by  transplanting  rabbit's 
cornea. 

This  posterior  elastic  lamina  sends  peripherally  radiating 
fibres  into  the  iris — ligamentum  pectinatum  iridis — and  in  this 
ligament  are  a  number  of  spaces  of  Fontana,  which  afford 
communication  between  the  anterior  chamber  and  the  canal 
of  Schlemm.  The  canal  of  Schlemm  is  a  circular  venous  sinus 
situated  at  the  junction  of  cornea  and  sclerotic,  and  embedded 
in  the  tissue  of  the  junction.  The  cornea  after  birth  has  no 
bloodvessels,  except  near  the  margin,  where  they  form  loops, 
but  is  nourished  by  abundant  lymph  streams  derived  from 


THE  EYE  65 

these  marginal  vessels,  and  returned  to  the  circular  venous 
channel  gr  canal  of  Schlemm. 

Despite  the  absence  of  bloodvessels,  the  cornea  has  a 
marked  vitality,  and  wounds  heal  readily,  sometimes  leaving 
no  subsequent  opacity.  Ulcers,  on  the  other  hand,  frequently 
cause  opacity,  owing  to  their  causing  considerable  destruction 
of  tissue,  which  is  replaced  by  connective  tissue.  Corneal 
ulcers  may  lead  to  perforation,  with  escape  of  the  aqueous 
humour  and  prolapse  of  the  iris,  which  may  become  adherent 
(anterior  synechice).  Vascularization  of  the1  cornea,  however, 
does  occur,  a  superficial  form  called  pannus  being  frequently 
associated  with  conjunctivitis,  while  a  deep  vascularization, 
generally  associated  with  keratitis,  may  also  occur,  and  is 
called  a  salmon  patch  when  the  vessels  form  close  leashes. 

The  cornea  is  richly  supplied  with  nerves,  derived  from  a 
plexus  round  its  periphery,  supplied  by  the  ciliary  nerves. 
The  branches  from  the  plexus  ramifying  in  the  cornea  have 
no  medullary  sheath.  In  consequence  of  the  rich  sensory 
nervous  supply,  inflammation  of  the  cornea,  keratitis,  is  pain- 
ful, and  accompanied  by  photophobia  or  intolerance  of  light. 
The  painfulness  gives  rise  to  excessive  lachrymation,  and  the 
photophobia  to  blepharospasm,  or  spasm  of  the  orbicularis 
muscle,  both  conditions  being  reflex.  In  glaucoma,  on  the 
other  hand,  the  pressure  on  the  nerves  produces  anaesthesia 
of  the  cornea.  Herpes,  or  zona  ophthalmica,  also  occurs 
occasionally  on  the  cornea. 

Arcus  senilis  is  a  degeneration  of  the  corneal  tissues,  con- 
fined to  the  periphery,  generally  appearing  as  a  crescent,  first 
in  the  upper  segment,  and  followed  by  a  second  in  the  lower 
segment,  the  two  fusing  later.  It  is  frequently  associated 
with  general  atheroma  of  the  vessels,  but  does  not  interfere 
with  the  healing  of  corneal  wounds. 

The  middle  coat  of  the  eyeball,  or  uveal  tract,  consists  of 
iris,  ciliary  body,  and  chorioid,  and  possesses  a  rich  vascular 
supply. 

The  IRIS,  or  diaphragm,  attached  peripherally  to  the  ciliary 
processes,  and  to  the  cornea  by  the  ligamentum  pectinatum 
iridis,  and  perforated  a  little  to  the  nasal  side  by  the  pupil, 
hangs  in  front  of  the  lens,  the  pupillary  margin  resting  upon, 
but  not  attached  to,  the  anterior  surface  of  the  lens  capsule. 
It  is  covered  by  epithelium  on  both  surfaces,  is  furnished  with 

5 


66  SURGICAL  ANATOMY 

sphincter  and  dilator  muscular  fibres,  and  is  pigmented.  In 
albinos  there  is  no  pigment,  and  the  red  colour  of  the  iris  is 
due  to  the  rich  vascular  supply.  In  blue  eyes  the  pigment 
is  confined  to  the  posterior  layers,  while  in  brown  eyes  it  is 
scattered  throughout.  In  some  cases  the  pupil  may  be 
displaced  peripherally  and  present  an  oval  outline  (corectopia) , 
or  more  than  one  pupil  may  be  present  (polycoria).  The 
peripheral  attachment  of  the  iris  is  not  a  very  strong  one,  and 
may  be  detached  by  injury  without  damage  to  the  other 
structures.  It  is-  also  easily  detached  in  the  operation  of 
iridectomy,  where  a  radiating  portion  of  iris  is  removed,  pro- 
ducing a  coloboma,  bleeding  being  arrested  by  muscular  con- 
traction. Congenital  coloboma,  due  to  persistence  of  the 
chorioidal  fissure,  generally  occurs  at  the  lower  and  inner 
quadrant.  After  removal  of  the  lens,  the  iris  loses  its  chief 
support,  and  becomes  '  tremulous.'  Congenital  absence  of  the 
iris,  irideremia,  may  occur. 

The  CILIARY  BODY  connects  the  periphery  of  the  iris  with  the 
chorioid.  In  structure  it  resembles  the  chorioid.  Imme- 
diately behind  the  iris  the  ciliary  body  is  thrown  into  a  series 
of  some  seventy  radiating  folds — the  ciliary  processes — and  is 
further  rendered  prominent  by  the  development  of  the 
ciliary  muscle  in  its  middle  coat.  The  ciliary  processes 
contain  large  tortuous  vessels,  are  covered  with  two  layers  of 
epithelium,  continuous  with  that  of  the  retina  (pars  ciliaris 
retinae),  and  are  supposed  to  secrete  the  aqueous  humour.  The 
ciliary  muscle  consists  chiefly  of  radial  fibres  springing  from 
the  junction  of  cornea  and  sclerotic,  and  from  the  ligamentum 
pectinatum,  to  be  inserted  into  the  ciliary  processes  and 
orbiculus  ciliaris  (q.v.).  Besides  giving  attachment  to  the 
iris  anteriorly,  the  ciliary  processes  give  attachment  to  the 
suspensory  ligament  of  the  lens  posteriorly.  The  lens  has  an 
inherent  tendency  to  become  more  convex,  but  is  prevented 
by  the  tension  kept  upon  it  by  the  capsule.  When,  however, 
by  a  contraction  of  the  ciliary  muscle  the  ciliary  processes 
are  pulled  forwards  and  inwards,  the  capsule  is  relaxed,  and 
the  lens  becomes  more  convex.  This  contraction  of  the 
ciliary  muscle  occurs  in  accommodation  for  near  objects,  and 
is  associated  with  contraction  of  the  pupil.  The  portion  of 
the  ciliary  body  nearest  the  chorioid  is  called  the  orbiculus 
ciliaris,  and  here  the  ciliary  processes  fade  into  a  large  number 


THE  EYE  67 

of  faintly  marked  radiating  ridges,  which  interdigitate  with 
others  i*  the  zonule  of  Zinn,  which  invests  the  vitreous  body 
at  this  part. 

The  CHORIOID,  which  is  the  most  extensive  part  of  the 
middle  coat,  reaching  from  the  entrance  of  the  optic  nerve 
to  about  y\  inch  from  the  corneal  margin,  consists  of  three 
layers.  The  outermost  layer,  or  stratum  vasculosum,  is  pig- 
mented,  and  contains  large  branches  of  the  short  posterior 
ciliary  arteries  and,  more  superficially,  large  veins,  which  in 
converging  form  whorls,  and  open  into  the  vena  vorticoscz. 
The  middle  coat,  or  lamina  chorio-capillaris,  is  composed  of 
capillaries,  while  the  innermost  layer,  or  lamina  basalts  (mem- 
brane of  Bruch),  is  transparent  and  almost  structureless. 

Externally  the  chorioid  is  in  contact  with  the  sclerotic,  to 
which  it  is  firmly  attached  at  the  point  of  entrance  of  the 
optic  nerve,  while  in  front  of  this  it  is  loosely  attached  by  the 
vessels  and  the  loose  lamina  fiisca.  Internally  it  is  in  contact 
with  the  pigmented  layer  of  the  retina.  Extensive  h&mor- 
rhage  from  injury,  or  sudden  decrease  of  intra-ocular  tension 
as  in  cataract  operations,  not  infrequently  occurs  between  the 
coats.  The  chorioid  may  be  ruptured  by  a  blow,  and  melanotic 
sarcoma  may  arise  from  it. 

Owing  to  its  rich  vascular  supply,  the  uveal  tract  is  particu- 
larly prone  to  inflammatory  affections.  Thus  iritis  is  not 
infrequently  seen  resulting  from  trauma  or  late  secondary 
syphilis.  Such  inflammations  are  apt  to  spread  to  the  ciliary 
region  (irido-cyclitis),  or  to  the  entire  uveal  tract,  destroying 
the  eyeball  (phthisis  bulbi),  and,  in  the  septic  type,  by  exten- 
sion along  the  lymphatics  of  the  optic  tract,  not  infrequently 
involves  the  other  eye  (sympathetic  ophthalmia).  Hence  ex- 
cision of  the  affected  eyeball  is  frequently  performed  as  a 
preventive  measure,  or  evisceration  of  the  globe,  leaving  the 
posterior  sclerotic  to  act  as  a  cup  for  the  artificial  eye,  may  be 
done  (Mule's  operation).  Owing  to  the  extensive  destruction 
which  is  apt  to  follow  septic  infection  of  the  ciliary  region,  it 
has  been  termed  the  dangerous  area  of  the  eye.  In  iritis 
the  anterior  ciliary  vessels  are  engorged,  producing  the 
characteristic  red  circumcorneal  zone ;  the  pupil  becomes 
contracted  from  spasm  ;  the  inflammatory  exudate  infiltrates 
the  iris  itself,  causes  adhesions  (posterior  synechicz)  to  the  lens, 
and  turbidity  of  the  aqueous  humour. 

5—2 


68  SURGICAL  ANATOMY 

The  RETINA  constitutes  the  innermost  of  the  three  coats  of 
the  eyeball.  Commencing  at  the  point  of  entrance  of  the 
optic  nerve,  which  lies  to  the  nasal  side  of  the  direct  optic 
axis,  it  ends  in  a  wavy  line,  the  ora  serrata,  a  short  distance 
behind  the  ciliary  body.  A  prolongation  from  the  retina, 
consisting  of  an  outer  pigmented  and  an  inner  epithelial  layer, 
is,  however,  continued  from  the  retina  beyond  the  ora  serrata 
over  the  ciliary  body  and  posterior  surface  of  the  iris,  and 
these  are  termed  the  pars  ciliaris  retince  and  pars  iridica 
retina  respectively.  The  retina,  in  which  the  fibres  of  the 
optic  nerve  are  spread  out,  consists  of  an  outer  pigmented 
layer,  which  is  attached  to  the  chorioid  externally,  and  an 
inner  nervous  layer,  which  is  in  contact  with  the  hyaloid 
membrane  of  the  vitreous  internally.  The  point  of  entrance 
of  the  optic  nerve,  or  blind  spot,  is  marked  by  the  optic  disc, 
which  is  slightly  raised  peripherally  and  cupped  centrally. 
The  optic  nerve,  like  the  other  cranial  nerves,  receives  a  sheath 
both  from  the  dura  and  the  pia-arachnoid,  and  these  sheaths 
extend  to  the  optic  disc.  Thus  intracranial  inflammatory  or 
congestive  conditions  may  easily  affect  the  optic  disc.  In 
optic  neuritis  the  optic  disc,  which  normally  is  well  defined 
and  of  a  faint  pink  tint,  which  contrasts  sharply  with  the  red 
reflex  of  the  fundus  generally,  becomes  swollen  and  blurred, 
while  the  vessels  become  engorged  and  tortuous.  Optic 
neuritis  occurs  in  cases  of  cerebral  tumour,  and  sometimes  of 
abscess,  and  is  said  to  be  due  to  intracranial  pressure.  Where 
optic  neuritis  has  persisted  it  may  be  followed  by  optic  atrophy, 
in  which  the  disc  is  sharply  defined  and  brilliantly  white,  while 
the  vessels  become  diminished  in  calibre.  In  glaucoma  the 
normal  cupping  of  the  disc  becomes  much  more  marked, 
forming  the  glaucomatous  cup. 

The  central  artery  of  the  retina,  which  supplies  the  retina 
with  blood,  runs  forward,  accompanied  by  its  vein,  in  the 
optic  nerve,  until  it  reaches  the  papilla,  where  it  divides  into 
an  upper  and  lower  branch,  each  of  which  again  almost  imme- 
diately divides.  As  the  anastomosis  of  the  central  artery  is 
almost  negligible,  complete  thrombosis  or  embolism  of  the 
central  artery  is  followed  by  blindness.  Both  upper  and  lower 
branches  of  the  artery  supply  blood  to  the  yellow  spot.  In 
embolism  of  the  central  artery  both  the  disc  and  the  vessels 
become  white. 


THE  EYE  69 

The  rriacula  lutea,  or  yellow  spot  of  the  retina,  is  situated  in 
the  direct  optical  axis,  is  somewhat  oval  in  shape,  raised  at 
the  margin,  and  presents  a  central  depression,  the  fovea 
centralis.  In  the  macula,  which  constitutes  the  region  of 
distinct  vision,  the  structure  of  the  retina  is  much  modified, 
till  in  the  fovea  only  the  layers  of  cones  and  of  cone  fibres  are 
present. 

The  retina  sometimes  becomes  detached  from  blows  on  the 
eyeball  and  idiopathically.  The  only  tumour  which  affects 
it  is  glioma,  which  occurs  in  young  children  and  is  very 
malignant.  It  increases  the  intra-ocular  tension  (secondary 
glaucoma),  and  may  cause  detachment  of  the  retina.  It 
involves  the  whole  eyeball,  and  causes  rupture,  with  formation 
of  a  fungus  haematodes,  and  also  involves  the  optic  nerve,  by 
which  it  may  extend  to  the  brain.  Secondary  deposits  may 
be  found  in  the  liver.  Retinitis  of  many  forms  occurs,  such  as 
haemorrhagic,  syphilitic,  and  albuminuric. 

The  space  between  cornea  and  lens,  which  is  occupied  by 
the  aqueous  humour,  is  divided  into  a  large  ANTERIOR  and  very 
small  POSTERIOR  CHAMBER  by  the  iris  The  AQUEOUS  HUMOUR 
is  secreted  by  the  ciliary  processes,  situated  behind  the  iris 
in  the  posterior  chamber,  passes  thence  between  lens  and  iris 
and  through  the  pupil  of  the  iris  into  the  anterior  chamber, 
where  it  is  absorbed  peripherally  by  the  spaces  of  Fontana, 
which  communicate  with  the  canal  of  Schlemm,  and  are 
situated  in  the  angle  between  cornea  and  iris  (filtering  angle). 

Glaucoma  is  a  disease  in  which  there  is  greatly  increased 
intra-ocular  tension.  This  increased  tension  is  caused  by 
obliteration  of  the  filtering  angle,  preventing  the  escape  of 
effete  aqueous  humour,  which  thus  accumulates.  It  occurs 
generally  in  old  persons,  and  is  associated  with  marked 
cupping  of  the  optic  disc,  which  is  surrounded  by  a  glauco- 
matous  ring.  Iridectomy  is  frequently  performed,  with  a 
view  to  restoring  the  filtering  angle,  and  thus  reducing  the 
pressure. 

The  LENS  is  situated  between  the  portion  of  the  eyeball 
containing  the  aqueous  humour  in  front  and  the  portion 
containing  the  vitreous  behind.  The  vitreous  humour,  en- 
closed in  its  hyaloid  envelope,  presents  anteriorly  a  deep 
concavity,  the  fossa  patellaris,  into  which  the  posterior  surface 
of  the  lens  fits.  The  lens  is  held  in  position  by  its  suspen- 


70  SURGICAL  ANATOMY 

sory  ligament,  derived  from  the  zonule  of  Zinn  (q.v.),  and  is 
enclosed  in  a  transparent  capsule.  This  capsule  separates  it 
from  the  aqueous  humour,  and  when  it  is  ruptured  by  trauma 
the  fluid  enters  the  lens,  causing  swelling  and  opacity  (trau- 
matic cataract).  The  posterior  surface  of  the  lens  is  more 
convex  than  the  anterior,  which,  however,  becomes  increas- 
ingly convex,  owing  to  the  elasticity  of  the  lens,  when  the 
capsule  is  relaxed  by  the  action  of  the  ciliary  muscle  in 
accommodation  for  near  objects.  This  elasticity  of  the  lens 
diminishes  with  age,  as  does  likewise  the  refractive  power,  and 
hence  the  near  point  (the  nearest  point  from  which  it  is  possible 
to  converge  the  rays  upon  the  retina)  becomes  more  distant. 
This  condition  is  known  as  presbyopia,  and  requires  for  its 
treatment  a  convex  lens.  In  later  life  diminished  energy  of 
the  ciliary  muscle  is  also  a  factor.  The  axis  of  the  lens  runs 
from  before  backwards  through  the  centre  of  the  pupil,  and  its 
extremities  are  termed  the  anterior  and  posterior  poles  of  the 
lens,  while  the  equator  of  the  lens  is  its  peripheral  circum- 
ference. Cataract  is  the  only  disease  of  the  lens.  It  consists 
of  an  opacity,  which  may  be  partial  or  complete.  The  partial 
forms  are  generally  congenital,  while  the  complete  are  most 
frequently  due  to  senile  changes,  but  also  arise  from  diabetes 
and  trauma,  especially  where  the  anterior  capsule  of  the  lens 
has  been  penetrated.  The  treatment  is  generally  extraction 
of  the  affected  lens,  a  strong  convex  lens  being  subsequently 
employed  to  correct  the  hypermetropia. 

The  VITREOUS  BODY,  consisting  of  a  transparent  gelatinous 
material,  occupies  the  portion  of  the  eyeball  between  lens  and 
retina,  which  constitutes  about  four-fifths  of  the  whole.  In 
shape  it  is  roughly  spherical,  save  for  the  patellar  fossa  in 
front,  and  it  is  enclosed  in  the  hyaloid  membrane,  which  is  in 
contact  with  the  internal  limiting  membrane  of  the  retina, 
and  adherent  to  it  at  the  optic  entrance.  In  front  of  the 
ora  serrata  the  hyaloid  membrane  becomes  thickened  and 
constitutes  the  zonule  of  Zinn.  The  zonule  presents  radiating 
ridges  alternating  and  fitting  between  those  of  the  ciliary 
processes.  The  ciliary  ridges  are  adherent  to  the. fossae  of 
the  zonule,  but  the  ciliary  fossae  are  not  adherent  to  the 
zonular  ridges,  lymph  spaces  intervening.  As  it  approaches 
the  equator  of  the  lens  the  zonule  splits  into  two  layers — an 
inner,  which  covers  the  anterior  portion  of  the  vitreous  and 


THE  EYE  71 

presentsvthe  fossa  patellaris,  and  an  outer  stronger  layer,  which 
blends  with  the  front  of  the  lens  capsule  near  the  equator 
and  constitutes  the  suspensory  ligament  of  the  lens.  The 
suspensory  ligament  is  fenestrated,  and  through  the  gaps  in  it 
the  fluid  in  the  anterior  chamber  can  communicate  with  the 
canal  of  Petit  (which  is  a  sacculated  lymph  space  surrounding 
the  equator  of  the  lens,  situated  behind  the  suspensory  liga- 
ment), and  also  with  the  fossae  between  the  ciliary  ridges. 
A  lymph  channel,  the  hyaloid  canal  of  Stilling,  which  repre- 
sents the  fcetal  hyaloid  artery,  runs  from  the  optic  papilla, 
through  the  vitreous,  to  the  posterior  surface  of  the  lens. 
Sometimes  the  hyaloid  artery  persists,  but  as  a  rule  special 
treatment  is  necessary  to  render  even  the  canal  of  Stilling 
visible.  The  vitreous  may  be  affected  by  extension  of  in- 
flammatory processes  from  other  parts  ;  by  suppurative  pro- 
cesses from  penetrating  wounds  or  the  lodgment  of  foreign 
bodies  ;  by  haemorrhages,  and  by  undue  fluidity.  It  may 
shrink  from  the  retina,  detachment  of  the  retina  frequently 
following.  Muscce  volitantes  are  frequently  complained  of  by 
rnyopics,  and  are  due  to  minute  remains  of  embryonic  tissue 
in  the  vitreous,  and  motes  are  also  frequently  seen  in  com- 
mencing cataract. 

The  eyeball  derives  its  BLOOD-SUPPLY  from  branches  of  the 
ophthalmic  division  of  the  internal  carotid.  These  consist  of 
(i)  central  artery  of  the  retina,  which  supplies  the  retina,  and 
anastomoses  slightly  at  its  margin  with  (2)  the  short  ciliary 
arteries,  some  eight  in  number,  which  pierce  the  sclerotic  near 
the  optic  nerve,  and,  breaking  up  into  a  capillary  plexus, 
supply  the  chorioid  ;  (3)  the  two  long  ciliary  arteries,  which, 
piercing  the  sclerotic  to  the  outer  side  of  the  optic  nerve,  run 
forward  to  the  base  of  the  iris,  anastomose  with  the  anterior 
ciliary,  and  form  the  circulus  arteriosus  major,  which  supplies 
the  ciliary  muscle,  and  send  branches  into  the  iris  to  form  the 
circulus  arteriosus  minor  ;  (4)  the  anterior  ciliary  arteries, 
small  twigs  from  the  muscular  and  lachrymal  branches  of  the 
ophthalmic,  which  penetrate  the  sclerotic  near  the  corneal 
junction,  and  anastomose  with  the  posterior  ciliary.  They 
supply  the  conjunctiva  and  the  plexus  round  the  circumference 
of  the  cornea.  This  plexus  is  normally  invisible,  but  in  iritis 
it  forms  a  pink  circumcorneal  zone  of  fine,  closely-set,  nearly 
parallel  vessels. 


72  SURGICAL  ANATOMY 

The  canal  of  Schlemm  is  a  circular  venous  channel  embedded 
in  the  corneo-scleral  junction,  which  communicates  with  the 
anterior  chamber  by  the  spaces  of  Fontana.  Its  blood  is 
removed  by  the  anterior  ciliary  veins,  which  fall  into  the 
venae  vorticosae. 

The  vence  vorticosce,  some  four  or  five  in  number,  are  the 
chief  veins  of  the  eyeball.  They  run  in  the  outer  layer  of  the 
chorioid  (external  to  the  arteries) ,  and  pierce  the  sclerotic  near 
the  equator  of  the  globe,  to  fall  into  the  ophthalmic  vein. 

The  NERVES  of  the  eyeball  are  derived  from  the  nasal  branch 
of  the  ophthalmic  of  the  fifth,  which  sends  in  two  long  ciliary 
nerves,  and  also  supplies  a  root  to  the  ciliary  ganglion  (sen- 
sory). The  motor  root  of  the  ganglion  is  supplied  by  the 
third  nerve,  and  there  is  also  a  sympathetic  root.  From  the 
ganglion  some  twelve  short  ciliary  nerves  pass  to  supply  the 
various  coats  of  the  eyeball,  the  third  nerve  enervating  the 
ciliary  muscle  and  the  circular  (contractor)  fibres  of  the  iris, 
and  the  sympathetic  the  radial  or  dilating  fibres  of  the  iris. 

In  inflammatory  affections  of  the  globe  pain  is  frequently 
referred  to  both  upper  branches  of  the  fifth,  affecting  the 
circumorbital,  nasal,  and  temporal  regions,  and  the  upper 
jaw  and  teeth,  and  is  accompanied  by  profuse  lachrymation 
and  blepharospasm  from  communications  between  the  fifth 
and  seventh  nerves.  Irritation  of  the  nasal  branch  of  the 
fifth  also  frequently  leads  to  watering  of  the  eye. 

The  PUPIL  is  contracted  by  the  third  nerve,  and  dilated  by 
the  cervical  sympathetic,  these  effects  being  involuntary, 
except  in  so  far  as  they  can  be  brought  into  action  by  accom- 
modation. Accommodation  is  required  for  near  objects,  the 
lens  being  rendered  more  convex  by  the  action  of  the  ciliary 
muscle,  acted  on  by  the  third  nerve,  while  the  iris  contracts. 
One  can  therefore  make  the  iris  contract  by  accommodating 
for  a  near  object.  In  locomotor  ataxy  the  reflexes  are  lost, 
and  therefore  the  pupil  will  not  contract  to  light,  as  such  con- 
traction is  reflex,  but  it  will  contract  on  accommodation  for 
near  objects,  as  accommodation  is  voluntary.  This  condition 
is  known  as  the  Argyll-Robertson  pupil. 

The  pupil  is  contracted  in  normal  sleep,  in  those  following 
occupations  necessitating  close  attention  to  small  work 
(weaver's  eye),  in  conditions  where  the  brain  is  engorged  with 
blood,  in  coma,  in  bleeding  under  the  tentorium,  and  in  small 


THE  EYE  73 

lesions  <tt  the  pons.  It  is  also  contracted  in  irritation  of  the 
third  nerve  or  paralysis  of  the  cervical  sympathetic.  Certain 
drugs  also  cause  contraction,  eserine  acting  locally,  morphia 
probably  both  locally  and  generally,  and  chloroform  and  alcohol 
(coma)  generally.  The  effect  of  CHLOROFORM  on  the  pupil  is 
of  particular  importance  surgically,  as,  when  the  pupil  is 
contracted  and  fixed  the  reflexes  are  abolished,  and  one  may 
safely  operate.  The  alcoholic  pupil  is  contracted,  but  not 
fixed,  as  it  will  slowly  dilate  on  stimulation  of  the  patient. 

The  pupil  is  dilated  in  nightmare,  generally  in  blindness,  in 
anaemia  of  the  brain,  faintness,  and  concussion.  It  is  also 
dilated  by  paralysis  of  the  third  nerve  or  irritation  of  the 
cervical  sympathetic.  Atropine  causes  dilatation  by  acting 
locally.  The  pupil  becomes  dilated  and  fixed  when  chloroform 
is  pushed  too  far,  and,  speaking  generally,  it  dilates  in  all 
cases  where  death  is  impending. 

The  ORBITAL  CAVITY,  consisting  of  a  strong  bony  margin 
anteriorly,  but  of  very  thin,  delicate  bones  internally,  is 
subject  to  fractures  and  to  affection  by  some  tumours.  The 
orbital  plate  of  the  frontal  is  frequently  broken  by  extension 
of  fractures  of  the  vault,  and  by  thrusts  of  sharp-pointed 
instruments  into  the  eyeball,  the  anterior  lobes  of  the  brain 
being  sometimes  thereby  involved.  Effused  blood  in  such 
cases  may  cause  proptosis,  and  ultimately  find  its  way  forward 
under  the  conjunctiva  and  under  the  eyelids.  It  is  distin- 
guished from  black  eye  by  its  much  slower  appearance,  its 
patchiness,  and  by  its  not  being  circumscribed  at  the  orbital 
margins.  The  inner  orbital  wall  may  be  similarly  fractured, 
and,  if  the  nasal  mucous  membrane  be  torn,  may  give  rise  to 
emphysema  of  the  orbital  tissues,  while  in  fracture  of  the 
inferior  orbital  wall  the  superior  maxillary  nerve  is  apt  to  be 
damaged,  and  the  antrum  of  Highmore  opened  into.  The 
outer  and  upper  margin  of  the  orbit  is  the  most  common  site 
of  dermoid  cysts.  Ivory  exostoses  sometimes  occur  about  the 
orbital  margin,  giving  rise  to  displacement  of  the  eyeball,  with 
proptosis.  Sarcomata  springing  from  the  orbit  itself,  or  in- 
vading it  from  the  antrum  of  Highmore,  the  base  of  the 
sphenoid,  or  the  temporal  or  zygomatic  fossae,  have  similar 
effects.  The  contents  of  the  orbital  cavity  consist  of  the 
eyeball,  optic  nerve,  muscles,  nerves,  and  vessels  ensheathed 
in  fatty  tissue  and  fascia. 


74  SURGICAL  ANATOMY 

THE  NOSE. 

The  skin  of  the  nose  is  thin  and  movable  over  the  nasal 
bones,  but  below  is  thick  and  adherent  to  the  cartilage,  and 
abundantly  supplied  with  sweat  and  sebaceous  glands.  The 
lower  portion  is  frequently  affected  by  acne  rosacea,  which  in 
cases  of  chronic  dyspepsia  sometimes  causes  considerable 
hypertrophy,  to  which  the  misleading  name  of  '  grog-blossoms  ' 
has  been  given.  Lipoma  nasi  is  a  diffuse  irregular  enlarge- 
ment of  the  same  portion,  all  the  tissues,  but  especially  the 
fatty  elements,  hypertrophying.  Suppurative  processes  in 
this  region  are  generally  very  painful,  owing  to  the  density 
of  the  tissue  and  the  abundant  nerve-supply.  The  upper  part 
is  supplied  by  the  infratrochlear  branch  of  the  nasal,  the  middle 
by  branches  of  the  infra-orbital,  and  the  lower  by  the  nasal. 
The  nasal  nerve,  being  a  branch  of  the  ophthalmic  of  the  fifth, 
explains  the  watering  of  the  eyes,  which  occurs  from  painful 
affections  of  the  nostril.  The  skin  of  the  nose  is  plentifully 
supplied  with  blood  by  branches  of  the  ophthalmic  and  facial 
arteries,  and  hence  healing  of  wounds  occurs  very  readily. 
Indeed,  a  portion  of  nose  which  had  been  cut  off,  but  kept 
warm,  has  been  successfully  stitched  on  after  an  interval  of 
nearly  half  an  hour.  On  the  other  hand,  on  account  of  its 
exposed  position,  the  nose  is  sometimes  affected  by  frost-bite. 
The  nose  tends  to  become  engorged  with  blood,  especially  in 
alcoholics,  and  sometimes  becomes  livid  in  persons  suffering 
from  obstructive  heart  disease,  etc.  While  rodent  ulcer  some- 
times attacks  the  skin  at  the  junction  of  the  ala  and  cheek, 
the  cartilaginous  portion  of  the  nose  is  not  infrequently 
destroyed  by  tubercular  (lupus)  and  syphilitic  ulcer ations. 
Each  ALA  of  the  nose  is  supported  by  an  upper  and  lower 
lateral  cartilage  and  several  accessory  cartilages.  The  upper 
cartilage  is  attached  to  the  nasal  bone  and  superior  maxilla, 
and  the  lower  one  does  not  extend  as  far  as  the  nostril.  A 
nasal  speculum  should  not  be  introduced  beyond  the  limits 
of  this  cartilaginous  portion.  Various  plastic  operations 
(rhinoplasty)  have  been  devised  to  remedy  defects  of  the  nose. 
In  the  Tagliocotian  operation  a  flap  is  raised  from  the  front 
of  the  upper  arm,  which  is  fixed  in  front  of  the  face,  and  not 
separated  from  the  arm  until  it  has  united  to  the  face.  A 
flap  also  has  been  cut  from  the  forehead,  and  turned  down  to 


THE  NOSE  75 

form  a  Hose,  the  frontal  artery  supplying  it  with  blood.  The 
NASAL  BONES  are  not  infrequently  fractured  by  direct  violence, 
especially  in  their  lower  third.  Such  fractures  are  generally 
accompanied  by  considerable  deformity,  and,  as  the  mucous 
membrane  of  the  nose  is  generally  lacerated,  are  compound. 
Free  epistaxis  and  emphysema  of  the  surrounding  tissues, 
especially  on  blowing  the  nose,  are  liable  to  occur.  As  the 
nasal  bones  heal  very  readily  (about  seven  days,  according  to 
Hamilton),  an  early  attempt  should  be  made  to  rectify  any 
deformity,  and  as  the  meatus  is  rendered  particularly  narrow 
by  the  swelling  of  the  parts,  only  a  fine  instrument  (stout 
probe)  should  be  introduced  to  aid  the  process.  In  some  very 
severe  injuries  the  nasal  septum  may  also  be  damaged.  The 
nasal'  bones  are  frequently  affected  in  infancy  by  hereditary 
syphilis,  causing  a  permanent  depression  of  the  bridge  of  the 
nose,  while  the  infant  also  '  snuffles.' 

The  NASAL  FOSS.E,  separated  by  the  septum,  include  the 
anterior  and  posterior  nares.  The  anterior  nares,  or  apertures 
of  the  nostrils,  are  small,  directed  downwards,  and  are  on  a 
lower  level  than  the  fossae.  The  posterior  nares,  choanae,  or 
posterior  outlets,  communicate  with  the  naso-pharynx. 

The  NASAL  SEPTUM  consists  of  the  nasal  spine  of  the  frontal 
bone,  vertical  plate  of  the  ethmoid,  rostrum  of  the  sphenoid, 
the  vomer,  and  the  palatal  crests  of  the  palate  and  superior 
maxillary  bones,  while  the  interval  is  filled  in  by  the  cartila- 
ginous septum. 

The  cartilaginous  nasal  septum  is  generally  deflected  after 
the  seventh  year,  due  probably  to  continuation  in  vertical 
growth  in  the  bones  after  they  have  met,  or  perhaps  to  the 
habit  of  blowing  the  nose  with  one  hand.  It  is  frequently 
attacked  in  acquired  syphilis,  producing  perforation  or  even 
destruction,  with  consequent  flattening  of  the  nose,  chrome- 
workers  sometimes  suffering  from  a  similar  affection.  Con- 
genital syphilis  generally  produces  a  depression  of  the  bridge 
of  the  nose,  and  both  forms  may  involve  the  bony  framework, 
sometimes  causing  perforation  of  the  hard  palate. 

The  roof  of  the  nasal  fossae  is  arched,  and  formed  anteriorly 
by  the  groove  in  the  nasal  bones,  then  by  the  cribriform  of 
the  ethmoid,  and  posteriorly  by  the  sphenoidal  turbinates. 
Its  narrowness  (J  inch)  protects  it  to  a  large  extent  from 
injury  from  all  but  sharp-pointed  instruments.  The  lym- 


76  SURGICAL  ANATOMY 

phatics  of  the  nose  run  along  the  sheaths  of  vessels  and  nerves 
through  the  cribriform  to  the  meninges,  and  thus  meningitis 
may  follow  a  septic  condition  in  the  nose. 

Fracture  involving  the  cribriform  plate  is  sometimes  asso- 
ciated with  escape  of  cerebro-spinal  fluid,  the  membranes 
being  ruptured.  Meningoceles  occasionally  protrude  through 
the  nasal  roof,  and  may  be  mistaken  for  polypi ;  but  they 
more  frequently  present  externally  at  the  root  of  the  nose 
through  the  suture  between  the  nasal  and  frontal  bones,  where 
they  have  been  mistaken  for  naevi. 

THE  OUTER  WALL. — Extending  upwards  and  inwards  from 
the  anterior  nares  to  the  bony  apertures  of  the  fossa  are  the 
vestibules,  which  are  lined  with  skin  containing  numerous  stout 
hairs  and  sebaceous  glands.  Skin  and  mucous  membrane 
meet  at  the  junction  of  vestibule  with  atrium,  which  latter 
leads  particularly  into  the  middle  meatus,  its  upper  portion 
leading  to  the  superior  meatus,  being  partially  cut  off  by  a 
prominence  known  as  the  agger  nasi. 

The  nasal  (Schneiderian)  membrane  is  covered  throughout 
by  columnar  ciliated  epithelium,  and  consists  of  olfactory  and 
respiratory  portions.  The  former  invests  the  upper  portion 
of  the  cavity  and  both  walls  to  the  level  of  the  centre  of  the 
middle  turbinate.  It  is  thin,  of  a  yellow  colour,  and  contains 
olfactory  glands  of  Bowman,  and  olfactory  cells  which  are 
directly  continuous  with  the  terminal  nerve  filaments  of  the 
olfactory  nerve,  and  end  in  olfactory  hairs.  The  respiratory 
portion  is  thick  and  more  vascular,  especially  over  the  lower 
borders  of  the  middle  and  inferior  turbinates,  where  the 
tissue  is  practically  cavernous.  The  portion  covering  the  in- 
ferior turbinate  is  called  the  erectile  body.  On  account  of  its 
vascularity  the  mucous  membrane  readily  becomes  congested, 
even  in  ordinary  colds,  causing  blocking  of  the  nose,  and  in 
long-continued  cases  gives  rise  to  a  hypertrophic  rhinitis.  The 
posterior  end  of  the  inferior  turbinate  is  particularly  prone 
to  hypertrophy,  and  may  project  into  the  posterior  nares, 
block  the  Eustachian  tube,  and  be  mistaken  for  a  tumour.  In 
ozcena,  or  atrophic  rhinitis,  there  is  a  persistent  purulent  dis- 
charge from  the  nostril,  the  offensive  nature  of  which  is  not 
perceived  by  the  patient,  as  his  sense  of  smell  is  lost.  In 
such  cases  it  is  frequently  necessary  to  wash  out  the  nose. 
This  is  done  by  use  of  the  nasal  douche,  the  nozzle  of  which 


THE  NOSE  77 

is  introduced  through  one  nostril,  while  the  patient  keeps  the 
mouth  wide  open.  The  palate  then  arches  up  and  shuts  off 
the  cavity  of  the  nose  from  the  pharynx,  and  so  the  fluid  runs 
up  one  nostril,  turns  posteriorly,  and  comes  down  the  other. 

Nasal  polypi  are  generally  myxomatous,  covered  with 
columnar  ciliated  epithelium,  and  grow  from  the  lower  border 
of  the  middle  turbinate.  Malignant  tumours  are  generally 
sarcomatous,  and  often  spring  from  the  base  of  the  skull, 
from  whence  they  invade  the  nasal  cavities,  distending  them 
and  giving  the  patient  a  '  frog  face.' 

The  blood-supply  is  derived  from  the  spheno-palatine  branch 
of  the  internal  maxillary  artery,  which  enters  the  fossa 
posteriorly  through  the  spheno-palatine  foramen  and  supplies 
the  outer  wall  and  septum,  and  also  from  the  ethmoidal 
branches  of  the  ophthalmic  and  small  branches  of  the  superior 
coronary  of  the  facial  and  of  the  descending  palatine  of  the 
internal  maxillary.  The  veins  carry  the  blood  forwards  to 
the  facial,  backwards  to  the  spheno-palatine,  and  upwards 
to  the  ethmoidal  veins.  These  latter  are  very  important,  as 
they  communicate  with  the  veins  of  the  dura  and  of  the  brain 
itself,  as  is  likewise  an  inconstant  communicating  vein  which 
runs  from  the  nose  through  the  foramen  caecum  to  the  superior 
longitudinal  sinus. 

The  lymphatics  lead  chiefly  to  the  deep  cervical  glands,  so 
that  retropharyngeal  abscess  may  arise  from  septic  infection 
of  the  nose,  but  those  from  the  olfactory  region  communicate 
with  the  subarachnoid  space.  Thus,  both  through  the  venous 
and  lymphatic  channels  mischief  may  reach  the  brain  from 
the  nose. 

Bleeding  from  the -nose,  or  epistaxis,  may  be  very  trouble- 
some and  profuse,  and  even  fatal.  The  fact  that  it  is  some- 
times checked  by  holding  the  hands  above  the  head  is  sup- 
posed to  be  due  to  the  increased  suction  action  of  the  chest 
lessening  the  venous  congestion. 

Beyond  the  atrium  the  outer  wall  is  complicated  by  the 
TURBINAL  BONES,  the  two  upper  of  which  belong  to  the 
ethmoid,  while  the  inferior  is  a  separate  bone.  These  bones 
project  inwards  and  downwards  from  the  outer  wall  toward 
the  septum,  which,  however,  they  do  not  touch,  a  space 
intervening,  through  which  part  of  the  inspired  air  passes. 
They  are  curled  on  themselves,  so  that  their  free  margins  are 


78  SURGICAL  ANATOMY 

directed  outwards.  They  each,  therefore,  roof  over  a  meatus, 
which  is  named  from  the  bone  which  forms  its  roof.  The 
superior  turbinal  is  the  smallest,  extending  forward  to  about 
the  centre  of  the  cribriform  ;  the  middle  turbinal  extends 
forward  to  the  level  of  the  anterior  end  of  the  cribriform  ;  while 
the  inferior  extends  anteriorly  to  within  J  inch  of  the  anterior 
nares  and  posteriorly  to  within  J  inch  of  the  Eustachian  tube. 
If  these  bones  be  removed,  the  meati  can  be  examined. 
The  SUPERIOR  MEATUS  is  very  small,  and  presents  apertures 
leading  into  the  posterior  ethmoidal  cells.  The  MIDDLE 
MEATUS  presents  anteriorly  a  thin  grooved  ridge  of  bone, 
curving  downwards  and  backwards.  This  is  the  uncinate 
process  of  the  ethmoid,  and  it  is  separated  from  the  bulla 
ethmoidalis  (a  rounded  prominence  containing  some  ethmoidal 
cells  which  lies  posteriorly  and  above  the  uncinate  process) 
by  a  deep  groove,  the  hiatus  semilunaris.  This  hiatus  opens 
along  its  outer  surface  into  the  infundibulum,  which  has  the 
same  boundaries  and  with  which  it  runs  parallel.  At  its  upper 
and  anterior  extremity  the  infundibulum  generally  receives 
the  fronto-nasal  duct  leading  from  the  frontal  sinus  and  the 
ostia  of  the  anterior  ethmoidal  cells.  At  its  lower  end, 
beneath  the  bulla,  and  concealed  by  the  uncinate  process, 
the  ostium  of  the  maxillary  sinus  opens  into  it.  One  or  two 
small  apertures  above  the  bulla  lead  to  the  middle  ethmoidal 
cells.  The  bulla  sometimes  hypertrophies,  presses  the  middle 
turbinal  against  the  septum,  which  may  yield,  thus  leading  to 
considerable  blockage  of  the  nose.  The  middle  meatus  has  a 
wide  anterior  opening,  which  favours  the  passage  of  inspired 
air  along  it,  and  in  passing  an  instrument  into  the  nose,  unless 
care  be  taken  to  keep  its  point  on  the  nasal  floor,  it  is  very 
apt  to  pass  into  the  middle  fossa.  The  INFERIOR  MEATUS 
has  a  curved  roof,  the  highest  point  being  at  the  junction  of 
its  anterior  and  middle  thirds.  At  this  point  also  the  outer 
wall  frequently  bulges  into  the  antrum,  thus  increasing  the 
size  of  the  meatus.  Here  the  nasal  duct  opens  by  a  narrow 
slit  close  to  the  meatal  roof,  f  inch  above  the  floor.  This 
height  of  the  meatus  should  be  kept  in  mind  in  introducing 
a  Eustachian  catheter,  which  might  not  pass  if  too  much 
curved.  The  floor,  composed  of  the  palatal  processes  of  the 
superior  maxillary  and  palate  bones,  is  over  J  inch  in  width, 
is  smooth,  slightly  concave  from  side  to  side,  and  slopes  gently 


THE  NOSE 


79 


,  •• 


FIG.  9. 


i     Brain  (frontal  lobe). 

2.  Frontal  sinus. 

3.  Ant.  ethmoidal  cells. 

4.  Post,  ethmoidal  cells. 

5.  Sphenoidal  sinus. 

6.  Sphenoid  bone. 

7.  Spheno-ethmoid  recess. 

8.  Superior  tneatus. 

9.  Fronto-nasal  duct. 

10.  Infundibulum. 

11.  Ethmoidal  bulla. 


—  DIAGRAM  OF  NASAL  CAVITY,  ETC. 
(-Modified  from  Turner,  etc.) 


12.  Cut  edge  of  middle  turbinal 

bone. 

13.  Processus  uncinatus. 

14.  Inferior  turbinate  bone. 

15.  Vestibule. 

16.  Hiatus  semilunaris. 

17.  Position  of  orifice  of  nasal 

duct. 

1 8.  Posterior    edge   of    nasal 

septum. 

19.  Orifice  of  Eustachian  tube. 


20.  Pharyngeal  tonsil. 

21.  Lateral  recess,  or  fossa  of 

Rosenmuller. 

22.  Palate. 

23.  Ant.  pillar  of  fauces. 

24.  Tonsil. 

25.  Post,  pillar  of  fauces. 

26.  Epiglottis. 

27.  Hyoid  bone. 

28.  Salpingo-pharyngeal  fold. 


downwards  and  backwards.  It  is  frequently  necessary  to 
plug  the  posterior  nares  in  cases  of  bleeding.  This  is  done  by 
passing  a  loop  of  stout  thread  by  means  of  a  special  sound  or 
ordinary  catheter  through  the  nose  to  the  pharynx,  where  it 


8o  SURGICAL  ANATOMY 

is  caught  from  the  mouth  and  drawn  forwards.  A  plug  of  a 
size  to  fit  the  posterior  nares,  which  measure  about  ij  inches 
vertically  and  J  inch  transversely,  is  then  fixed  to  the  loop,  by 
which  it  is  drawn  up  into  the  nares.  The  ends  are  then  tied 
to  another  plug  applied  over  the  nostril.  It  is  well  to  attach 
a  single  thread  to  the  plug  for  the  posterior  nares  before 
pulling  it  into  position,  by  which  it  may  be  withdrawn  when 
done  with.  The  nasal  cavities  may  be  explored  by  passing 
one  finger  up  the  nostril  and  another  through  the  mouth,  and 
polypi  may  sometimes  be  so  removed.  Where  it  is  necessary 
to  get  a  full  view  of  the  nares  an  almost  median  dorsal  vertical 
incision  may  be  made  through  the  nostril  (Kocher),  or  the 
upper  lip  may  be  everted,  mucous  membrane  incised,  and  soft 
parts  shelled  up  (Rouge).  An  ordinary  examination  may  be 
made  by  introducing  a  speculum,  elevating  the  nostril  and 
tip  of  the  nose,  and  using  a  forehead  mirror.  The  posterior 
nares  may  be  inspected  by  posterior  rhinoscopy,  using  the 
forehead  mirror  and  a  small  laryngeal  mirror  introduced 
through  the  mouth  behind  the  soft  palate.  Foreign  bodies 
are  not  infrequently  found  in  the  nose,  some  of  which  may 
have  lodged  there  for  many  years,  and  these  sometimes  form 
the  nucleus  for  a  deposition  of  calcareous  matter,  such  masses 
being  called  rhinoliths.  The  olfactory  nerve  supplies  the  upper 
or  olfactory  portion  of  the  nose,  and,  as  little  air  passes 
through  this  portion  in  ordinary  respiration,  it  is  usual  to 
sniff  when  endeavouring  to  perceive  an  odour.  The  loss  of 
ability  to  dilate  the  nostril,  as  in  sniffing,  may  explain  the 
partial  loss  of  smell  in  facial  paralysis.  As  already  explained, 
the  relationship  of  the  nerve  supply  of  the  eye  and  nose 
derived  from  the  ophthalmic  of  the  fifth  is  very  close.  Thus, 
when  the  nose  is  irritated  the  eye  waters,  as  in  taking  snuff, 
and  when  the  eye  is  exposed  to  bright  sunlight  sneezing  is 
sometimes  produced.  In  nasal  obstruction,  not  merely  is 
respiration  interfered  with,  but  the  voice  is  altered,  and  smell 
and  taste  suffer,  while  a  form  of  asthma  also  sometimes 
develops.  This  asthma  is  probably  due  to  a  reflex  from  the 
fifth  along  fibres  of  the  vagus  derived  from  the  fifth,  and  is 
generally  cured  on  removal  of  the  nasal  obstruction. 

The  ACCESSORY  SINUSES  of  the  nose  are  important  on 
account  of  their  frequent  involvement  in  nasal  affections. 
The  sinuses  to  be  considered  consist  of  two  groups — a  posterior, 


THE  ACCESSORY  SINUSES  81 

opening  above  the  middle  turbinate,  and  consisting  of  the 
sphenoicfal  and  posterior  ethmoidal ;  and  an  anterior,  opening 
below  the  middle  turbinate,  and  consisting  of  anterior  eth- 
moidal, frontal,  and  superior  maxillary.  With  the  exception 
of  the  ethmoidal  cells,  which,  unlike  the  others,  are  not 
formed  by  absorption  of  diploic  cancellous  bone,  these  sinuses 
are  either  non-existent  or  rudimentary  at  birth — the  antrum 
of  Highmore,  for  example,  consisting  of  a  slit-like  indentation. 

The  Posterior  Group. — The  SPHENOIDAL  SINUSES  occupy  the 
anterior  portion  of  the  body  of  the  sphenoid,  and  are  separated 
from  one  another  by  an  osseous  septum.  Occasionally  one 
or  both  may  be  absent,  and  they  vary  considerably  in  size. 
When  large,  the  olfactory  peduncle,  optic  commissure,  pitui- 
tary body,  and  pons  lie  on  the  thin  roof,  while  the  optic  nerve 
and  ophthalmic  artery  lie  on  the  superior  external  aspect,  and 
the  internal  carotid  artery,  cavernous  sinus,  and  structures 
occupying  the  sphenoidal  fissure  are  in  relation  to  the  external 
lateral  wall.  The  floor  is  sometimes  thin,  and  under  it  lies 
the  Vidian  nerve.  The  sinus  is  sometimes  invaded  by  tumours 
of  the  pituitary,  and,  on  the  other  hand,  septic  conditions  of 
the  sinus  may  lead  to  involvement  of  the  optic  nerves,  caver- 
nous sinus,  etc.  The  ostium  is  situated  on  the  anterior  wall, 
near  the  roof,  and  opens  into  the  spheno-ethmoid  recess  on 
the  internal  surface  of  the  superior  turbinate.  It  does  not, 
therefore,  facilitate  drainage  ;  it  is  sometimes  so  small  that  it 
will  not  admit  a  probe,  and  it  is  generally  necessary  to  remove 
a  portion  of  the  middle  turbinate  before  an  instrument  can 
reach  it  from  the  nose.  It  lies  fully  3  inches  from  the  nasal 
vestibule,  at  an  angle  of  nearly  45  degrees  upwards  and  back- 
wards from  the  nasal  floor. 

The  ETHMOIDAL  CELLS,  situated  in  the  lateral  mass  of  the 
ethmoid,  vary  in  number  and  size,  and  are  divided  into 
posterior  and  anterior  sets,  which,  as  a  rule,  do  not  com- 
municate, by  an  oblique  lamina  of  bone.  Externally  they 
are  bounded  by  the  os  planum  of  the  ethmoid,  internally  by 
the  superior  and  middle  turbinates,  above  by  the  orbital 
plate  of  the  frontal,  and  below  by  the  orbital  plate  of  the 
superior  maxilla.  Anteriorly  they  are  closed  in  by  the  nasal 
process  of  the  superior  maxilla  and  the  lachrymal  bone,  and 
posteriorly  by  the  sphenoidal  spongy  bones. 

The  posterior  ethmoidal  cells  rarely  communicate  with  the 

6 


82  SURGICAL  ANATOMY 

sphenoidal  sinus,  but  sometimes  project  into  the  body  of  the 
sphenoid,  giving  rise,  when  infected,  to  symptoms  similar  to 
those  of  sphenoidal  sinus  infection. 

These  cells  open  into  the  superior  meatus  by  one  or  more 
ostia  and  are  very  inaccessible.  A  purulent  discharge  may 
find  its  way  posteriorly  into  the  naso-pharynx  or  anteriorly 
into  the  nose. 

The  anterior  ethmoidal  cells  are  closely  related  to  the  floor 
of  the  frontal  sinus,  in  which  they  not  infrequently  form  a 
projection  called  the  bulla  frontalis.  They  may  also  project 
upwards  along  the  roof  of  the  orbit,  and  downwards  into  the 
roof  of  the  antrum  of  Highmore,  and  may  thus,  when  infected, 
cause  symptoms  simulating  disease  of  these  sinuses,  which 
may  actually  become  involved  by  destruction  of  the  thin 
bony  septa. 

The  ethmoidal  bulla,  already  spoken  of,  situated  at  the 
antero-inferior  border  of  the  lateral  mass,  also  contains  one 
or  more  cells,  and  further  cells  may  be  found  in  the  middle 
and  inferior  turbinate  bones.  These  latter  (owing  to  blockage 
of  the  duct  in  nasal  catarrh)  sometimes  become  transformed 
into  mucoceles,  which  may  be  so  large  as  to  obstruct  the  nasal 
passage. 

Several  ostia  open  into  the  infundibulum  on  its  outer  and 
posterior  aspect,  and  not  infrequently  the  infundibulum  itself 
originates  in  the  cells  forming  the  bulla  frontalis.  Other  ostia 
open  directly  into  the  middle  meatus.  Inflammatory  con- 
ditions of  the  cells  are  frequently  associated  with  the  presence 
of  soft  polypi  in  the  nose,  and  with  dacryocystitis  (inflamma- 
tion of  the  lachrymal  sac),  while  extension  to  the  orbit  or 
cranial  cavity  is  to  be  feared. 

The  FRONTAL  SINUSES  are  situated  immediately  above  the 
root  of  the  nose,  between  the  tables  of  the  frontal  bone.  They 
are  separated  by  a  septum  and  vary  greatly  in  size,  to  which 
the  prominence  of  the  superciliary  ridge  is  no  guide.  Some- 
times one  or  both  are  absent.  One  sinus  is  often  much  larger 
than  the  other  ;  the  cavities  are  frequently  subdivided  by 
incomplete  septa,  and,  while  the  main  septum  is  generally 
mesial,  it  is  sometimes  deflected.  If  a  sinus  be  present  it  can 
generally  be  reached  by  making  a  horizontal  skin  incision  at 
the  level  of  the  eyebrow,  and  going  down  immediately  above 
the  root  of  the  nose  in  the  angle  between  the  middle  line  and 


THE  ACCESSORY  SINUSES  83 

the  inner,,  third  of  the  supra-orbital  margin.  Care  should  be 
taken  to  clear  out  all  the  subdivisions  of  the  sinus.  The 
posterior  wall  of  the  sinus  is  in  relation  to  the  frontal  lobe  of 
the  brain,  and  the  floor  forms  part  of  the  roof  of  the  orbit. 

Inflammatory  conditions  of  the  sinuses  may  involve  the 
brain,  and,  where  the  bone  is  affected,  perforation  often  takes 
place  at  the  inner  angle,  the  eyeball  being  pushed  down  and 
outwards,  and  diplopia  resulting.  Not  infrequently  the  orbital 
cavity  is  involved  in  disease,  tubercular  or  otherwise,  originat- 
ing in  the  sinus,  the  pus  generally  pointing  at  the  inner  side 
of  the  upper  eyelid.  The  sinuses  may  be  fractured  without  the 
cranial  cavity  being  involved,  and  emphysema  of  the  sur- 
rounding tissues  may  arise  therefrom  when  the  mucous  mem- 
brane is  torn. 

The  fronto-nasal  duct,  which  varies  much  in  size,  begins 
at  the  lowest  part,  close  to  the  septum,  thus  favouring  drainage. 
It  may  open  into  the  infundibulum  or  into  the  middle  meatus 
direct,  the  ostium  varying  from  a  slit  to  an  aperture  J  inch 
in  diameter.  The  introduction  of  a  probe  is  not  always  an 
easy  matter,  it  being  frequently  necessary  to  remove  the 
middle  turbinate,  while  the  probe  is  also  liable  to  enter  the 
ostia  of  the  anterior  ethmoidal  cells. 

The  ANTRUM  OF  HiGHMORE  presents  three  walls,  a  roof,  and 
a  floor.  The  anterior,  or  facial  wall,  is  limited  externally  by 
the  malar  ridge,  and  below  by  the  alveolar  border.  It  is 
thin,  and  presents  a  prominence  for  the  canine  tooth,  which  is 
separated  from  the  molar  ridge  by  the  canine  fossa,  and  the 
infra-orbital  canal,  which  transmits  the  infra-orbital  vessels  and 
nerves.  The  position  of  the  latter  may  be  defined  by  taking 
a  point  on  Holden's  line  (drawn  from  the  supra-orbital  notch 
to  the  internal  between  the  bicusp  teeth  of  both  jaws),  J  inch 
below  the  lower  orbital  margin.  The  nasal  wall  forms  the 
outer  boundary  of  the  inferior  and  middle  meati.  The 
portion  bounding  the  inferior  meatus  is  osseous,  and  is  thinnest 
immediately  beneath  the  attachment  of  the  inferior  turbinate, 
where,  at  a  point  |  inch  behind  its  anterior  extremity,  the 
antrum  is  best  tapped  from  the  nose.  Above  the  inferior 
turbinate  the  wall  is  partly  osseous  and  partly  membranous, 
and  presents  the  ostium,  which  opens  into  the  antrum  close 
to  its  roof,  and  into  the  nose  at  the  most  dependent  portion 
of  the  infundibulum.  It  therefore  follows  that  suppurative 

6—2 


84  SURGICAL  ANATOMY 

processes  in  the  frontal  sinus  or  anterior  ethmoidal  cells  are 
very  apt  to  secondarily  infect  the  antrum  of  Highmore,  the 
pus  travelling  down  the  naso-frontal  duct  to  the  infundibulum, 
and  thence  through  the  maxillary  ostium.  Once  the  pus 
enters  here,  it  does  not  readily  escape,  owing  to  the  position 
of  the  ostium,  save  when  the  head  is  laid  on  the  opposite  side, 
the  pus  then  frequently  coming  away  in  a  gush.  The  ostium 
varies  in  size,  but  averages  J  inch  vertically  and  J  inch  antero- 
posteriorly.  Not  infrequently  an  accessory  ostium  is  present, 
and  is  sometimes  the  larger  of  the  two.  When  present  it  is 
situated  below  the  other,  and  facilitates  the  escape  of  pus 
into  the  throat.  Neither  ostium  is  easily  reached  from  the 
nares  by  catheter. 

The  roof  forms  the  floor  of  the  orbit,  is  thin,  and  presents 
the  canal  from  the  superior  maxillary  nerve  and  vessels.  This 
canal  is  sometimes  invaded  or  crushed  in  antral  disease, 
giving  rise  to  severe  neuralgia,  while  later  the  tumour  or  pus 
may  invade  the  orbital  cavity  or  ethmoidal  cells.  The  floor 
is  the  alveolar  border  of  the  superior  maxilla,  and  is  on  the 
same  level  as  the  nasal  floor.  The  bone  is  generally  thinnest 
over  the  fangs  of  the  first  and  second  molars,  while  the  fang 
of  the  canine  generally  lies  in  front  of  the  antrum.  Probably 
the  second  molar  bears  the  most  constant  close  relation  to 
the  antrum,  a  point  to  bear  in  mind  in  entering  the  antrum 
from  the  mouth.  Disease  of  the  fangs  of  the  molar  teeth 
sometimes  gives  rise  to  antral  suppuration.  The  antrum 
varies  much  in  size,  and,  where  small,  the  walls,  particularly 
the  alveolar,  are  thicker,  and  vice  versa.  When  large  the  cavity 
may  extend  mesially  into  the  palatal  plate  of  the  maxilla. 
The  walls  are  supplied  by  blood  from  the  periosteum,  which 
lines  both  the  inner  and  outer  surfaces,  and  from  the  walls 
numerous  septa  pass  into  the  cavity,  thus  partially  sub- 
dividing it.  This  subdivision,  combined  with  the  position  of 
the  ostium,  renders  antral  suppuration,  as  a  rule,  intractable. 
It  has  already  been  stated  that  the  antrum  may  be  reached 
through  the  nose  or  through  the  socket  of  one  of  the  molars. 
Probably  the  most  efficient  mode  of  dealing  with  antral 
suppuration,  however,  is  to  evert  the  upper  lip,  cut  through 
the  junction  of  gum  and  lip,  and  shell  all  the  tissues  upwards 
with  a  periosteal  elevator  until  close  to  the  infra-orbital 
foramen,  when  an  opening  can  be  made  by  trephine  or  simply 


THE  FACE  85 

crushing^in  the  canine  fossa.  This  opening  may  be  sufficiently 
large  to  permit  of  thorough  exploration  and  removal  of 
disease,  but  if  a  permanent  opening  be  required,  it  is  best 
made  through  the  nose. 

THE  FACE. 

The  SKIN  of  the  face  varies  in  character  at  different  parts. 
In  the  orbital  region  it  is  very  thin,  and  possesses  but  little 
subcutaneous  tissue  ;  in  the  cheeks  it  is  thicker,  and  possesses 
a  single  thick  layer  of  subcutaneous  tissue,  which  extends  down 
to  the  periosteum  of  the  bone,  and  contains  much  fatty  tissue. 
A  special  pad  of  fat  which  lies  between  the  anterior  border  of 
the  masseter  and  outer  aspect  of  the  buccinator,  and  which 
is  separated  from  the  rest  of  the  fatty  tissue  of  the  cheek 
by  a  layer  of  fascia  from  the  parotid  capsule,  is  known  as  the 
sucking  or  buccal  pad  of  Bichat.  It  is  not  much  affected  in 
general  emaciation,  and  accordingly  becomes  very  prominent, 
especially  in  emaciated  children.  In  the  lips  and  chin  the 
skin  is  thick,  and  the  subcutaneous  tissue  is  largely  occupied 
by  muscular  tissue.  The  skin  of  the  face  is  richly  supplied 
with  fat  and  sweat  glands,  and  is  a  common  seat  of  acne. 

Superficial  abscesses  are  generally  small,  while  subcutaneous 
effusions  can  spread  readily  in  the  lax  tissues  of  the  eyelids 
and  cheeks,  but  meet  with  resistance  in  the  chin.  The  swelling 
of  the  lower  eyelid,  which  occurs  in  some  renal  conditions,  is 
well  known.  Cancrum  oris,  a  rapidly  progressing  gangrene 
seen  occasionally  in  neglected  children,  begins  on  the  inside 
of  the  cheek,  and  rapidly  spreads  to  the  outside  and  peripher- 
ally, causing  complete  destruction  of  the  parts.  Malignant 
pustule,  caused  by  anthrax,  frequently  affects  the  face. 
Rodent  ulcer  frequently  attacks  the  parts  above  a  line 
drawn  from  the  nostril  to  the  lobe  of  the  ear,  while  lupus 
affects  the  parts  below  this  line.  The  face  is  richly  supplied 
with  blood  by  the  facial  artery,  which,  arising  from  the 
external  carotid,  crosses  the  lower  jaw  along  the  anterior 
border  of  the  masseter,  the  vein  lying  some  distance  posterior. 
It  runs  up  toward  the  angle  of  the  mouth,  and  then  to  the 
inner  canthus  of  the  eye,  its  course  being  very  tortuous,  and 
many  branches  being  given  off,  which  anastomose  with 
(a)  those  of  the  opposite  side,  (b)  branches  from  the  temporal 


86  SURGICAL  ANATOMY 

and  internal  maxillary,  and  (c)  ophthalmic  of  the  internal 
carotid.  Bleeding  from  wounds  of  the  face  is  accordingly 
free,  it  being  frequently  necessary  to  secure  both  ends  of 
a  divided  vessel.  Ncevi,  both  capillary  and  cavernous,  not 
infrequently  affect  the  face,  especially  the  lips.  The  facial 
vein  is  of  importance,  as  it  has  no  valves,  tends  to  remain 
patent  on  section,  and  because  it  communicates  with  the 
internal  jugular  in  the  neck,  and  with  the  cavernous  sinus, 
both  (a)  through  the  angular  vein,  which  communicates  with 
the  superior  ophthalmic  vein,  which  opens  into  the  sinus,  and 
(b)  through  the  deep  facial  vein,  which  runs  to  the  pterygoid 
plexus,  which  is  connected  with  the  cavernous  sinus  by  little 
veins  traversing  the  foramen  ovale.  Thus,  septic  affections 
of  the  face  may  readily  give  rise  to  great  septic  absorption 
and  sinus  thrombosis.  The  lymphatics  of  the  inner  portions 
of  the  face  drain  chiefly  to  the  subm axillary  and  superficial 
cervical  glands,  while  the  outer  portions  drain  to  the  parotid 
region. 

Congenital  cavernous  lymphangiomata  are  occasionally  met 
with  in  the  face. 

Nerve-Supply. — The  facial  is  the  motor  nerve  of  the  face. 
Having  traversed  the  temporal  bone,  it  emerges  at  the  stylo- 
mastoid  foramen,  runs  forwards,  and  forms  the  pes  anserinus 
in  the  parotid  gland,  from  which  radiating  branches  are  given 
off.  A  unilateral  FACIAL  PARALYSIS  may  result  from  an 
affection  of  (a)  centre  in  the  brain,  when  the  side  of  the  face 
affected  is  opposite  to  that  of  the  lesion  and  the  paralysis  is 
incomplete,  the  mimetic  play  of  the  features  being  retained  ; 

(b)  the  nerve  in  the  temporal  bone,  where  the  paralysis  is  on 
the  same  side  and  is  complete  once  the  nerve  is  destroyed  ; 

(c)  an  affection  of  the  peripheral  portion  of  the  nerve  from 
exposure  to  cold  :  here  the  paralysis  comes  on  suddenly,  and 
is   generally   complete,    and   often   very   intractable.     In   a 
complete  paralysis  of  one  side  the  eyelid  cannot  be  closed ; 
the  eyeball  appears  prominent ;  tears  may  overflow  on  to  the 
cheek  (epiphora)  from  drooping  of  the  lower  eyelid  and  corneal 
irritation,  and  the  brow  droops ;  the  natural  furrows  of  the 
face  disappear  ;  the  nostril  does  not  expand  on  inspiration,  and 
hence  sense  of  smell  is  impaired ;  the  patient  cannot  whistle  ; 
he  frequently  complains  that  when  taking  fluid  the  material 
runs  out  of  the  corner  of  his  mouth ;  and  when  he  smiles,  the 


THE  FACE  87 

muscles,,  of  the  unaffected  side  draw  the  affected  portions 
toward  them,  and  thus  cause  distortion.  Speech,  also,  is 
generally  thick.  In  incomplete  facial  paralysis,  on  the  other 
hand,  while  the  patient  may  be  unable  to  close  the  eye 
voluntarily,  he  generally  does  so  bilaterally,  as  in  blinking, 
and  when  he  smiles,  the  affected  side  of  the  face  responds 
slightly  and  is  not  mask-like.  The  sensory  nerve -supply  is 
from  the  trigeminal,  of  which  the  ophthalmic  division  supplies 
the  brow,  nose,  canthi,  and  upper  eyelid ;  the  superior 
maxillary  division  supplies  the  lower  eyelid,  cheek,  side  of  nose, 
and  upper  lip  ;  the  inferior  maxillary  division  supplies  the 
skin  of  the  temporal  region,  that  covering  the  masseter 
muscle,  lower  lip,  and  chin,  and  the  mucous  membrane  of  the 
cheek  and  lower  lip. 

The  supra-orbital  nerve  comes  out  through  the  supra-orbital 
foramen,  at  the  junction  of  the  middle  and  inner  thirds  of  the 
upper  orbital  margin.  A  line  drawn  from  this  to  the  interval 
between  the  bicusps  of  both  jaws  (Holden's  line)  passes 
through  the  infra-orbital  foramen,  which  lies  about  J  inch 
below  the  lower  orbital  margin,  and  through  the  mental 
foramen,  which  transmits  the  terminal  branches  of  the  third 
division,  and  which  lies  midway  between  the  alveolus  and 
lower  border  of  the  jaw. 

Facial  neuralgia  may  be  caused  by  affections  of  the  Gas- 
serian  ganglion,  which  give  rise  to  a  severe  trigeminal  type  ; 
by  tumours,  such  as  sarcomas,  springing  from  the  base  of 
the  skull,  or  osteomas  projecting  into  one  of  the  nerve  canals  ; 
or  by  peripheral  irritation,  such  as  caries  of  the  teeth  or  in- 
flammatory conditions  surrounding  the  exit  of  one  of  the 
foramina. 

Sometimes  the  neuralgia  gives  rise  to  spasms  (tic  douloureux), 
and  is  frequently  associated,  when  severe,  with  flushing  and 
swelling  of  the  affected  parts  and  watering  of  the  eye  and 
nose,  and,  as  these  parts  are  then  extremely  sensitive,  the 
patient's  condition  is  very  miserable.  In  severe  trigeminal 
cases  it  is  generally  necessary  to  excise  the  Gasserian  ganglion, 
and  this  operation,  if  successful,  is  followed  by  complete 
relief.  Sometimes,  also,  Meckel's  ganglion  is  removed,  or 
peripheral  portions  of  the  nerves  excised,  as  a  rule  with  only 
temporary  success,  unless  the  cause  be  peripheral.  Meckel's 
ganglion  lies  in  the  spheno-maxillary  fossa,  and  is  generally 


88  SURGICAL  ANATOMY 

reached  by  following  up  the  infra-orbital  nerve  and  artery 
(Carnochan's  operation).  The  ganglion,  a  small  reddish  body 
about  I  inch  in  diameter,  lies  in  front  of  the  foramen  rotundum, 
and  the  Vidian  canal  of  the  sphenoid  (which  transmits  the 
Vidian  nerve  to  the  ganglion)  below  the  second  division  of 
the  fifth  nerve.  To  its  outer  side  lie  the  terminations  of  the 
internal  maxillary  artery,  the  external  pterygoid  muscle,  and 
the  pterygo-maxillary  fissure  (which  communicates  with  the 
fossa  of  that  name),  and  to  its  inner  side  the  vertical  plate 
of  the  palate  and  the  spheno-palatine  foramen  (which  com- 
municates with  the  nasal  fossa  and  transmits  the  artery  of 
that  name)  and  the  nasal  branches  of  the  ganglion.  In  addi- 
tion to  orbital  and  nasal  branches,  it  gives  off  three  palatine 
nerves — anterior,  posterior,  and  external — which  supply  the 
palate,  posterior  arch  of  the  fauces,  and  tonsil.  As  the 
branches  of  the  fifth  overlap  one  another  in  distribution, 
excision  of  a  division  is  followed  by  very  limited  anaesthesia. 

The  face  is  developed  from  five  processes  :  an  upper  central, 
or  fronto-nasal ;  two  upper  lateral,  or  maxillary  ;  and  two  lower 
lateral,  or  mandibular.  The  fronto-nasal  process  grows  down 
and  forms  the  nose,  central  portion  of  the  upper  lip,  and  pre- 
maxilla,  which  carries  the  upper  central  incisor  teeth.  The 
maxillary  processes  grow  inwards  and  join  the  fronto-nasal 
process,  forming  the  upper  jaw,  cheek,  and  palate,  while  the 
mandibular  processes  grow  inwards,  fuse  centrally,  and  form 
the  lower  jaw.  A  hare-lip  is  produced  when  the  fronto-nasal 
and  maxillary  processes  do  not  fuse  properly  at  their  lower 
extremities.  A  coloboma  facialis  is  produced  by  a  want  of 
union  between  the  fronto-nasal  process  and  the  superior 
maxillary  process  throughout  their  length.  It  presents  below 
as  an  ordinary  hare-lip,  then  passes  up  around  the  ala  of  the 
nose  to  the  orbital  cavity,  forming  a  coloboma  of  the  lower 
eyelid.  Macrostoma,  or  transverse  facial  cleft,  is  a  partial 
persistence  of  the  cleft  between  the  maxillary  and  mandibular 
processes,  and  extends  upwards  and  outwards  from  the  angle 
of  the  mouth.  Microstoma  is  produced  by  excessive  union  of 
the  processes. 

THE  UPPER  JAW.— While  composed  largely  of  thin  bone, 
and  containing  the  antrum  of  Highmore,  the  upper  jaw,  owing 
to  the  arrangement  of  buttresses  by  which  the  force  of  blows 
is  distributed,  is  not  frequently  fractured.  In  severe  blows 


UPPER  JAW  AND  PAROTID  REGION  89 

on  the  mfalar  bone  the  zygoma  may  give  way  and  the  malar 
be  driven  into  the  antrum,  and  in  fractures  of  the  superior 
maxilla  the  infra-orbital  nerve  may  be  caught,  or  involved 
subsequently  in  callus,  or  the  lachrymal  sac  may  be  torn. 
The  maxilla  tends  to  heal  readily,  with  minimal  callus  forma- 
tion. The  upper  jaw  may  be  involved  primarily  or  second- 
arily by  tumours,  particularly  sarcomata.  These  frequently 
invade  the  antrum,  which  is  distended,  giving  rise  to  neuralgia, 
and  later,  when  the  orbital  cavity  is  involved,  to  exophthal- 
mos  and  diplopia,  owing  to  the  displacement  of  the  affected 
eyeball. 

Frequently,  also,  the  palate  becomes  involved,  the  teeth 
may  come  out,  and  the  fungating  mass  project  into  the 
mouth,  while  it  may  also  project  backwards  and  inwards  to 
the  naso-pharynx.  Where  the  disease  is  not  very  extensive, 
it  may  be  treated  by  excision  of  the  upper  jaw,  in  which  the 
greater  portion  of  the  jaw,  together  with  portions  of  the 
malar,  lachrymal,  ethmoid,  and  palate,  is  removed.  It  is 
desirable,  wherever  possible,  to  save  the  floor  of  the  orbit,  in 
order  to  preserve  the  eyeball  in  its  proper  position,  and,  where 
this  can  be  done,  the  operation  is  generally  followed  by  but 
little  deformity.  The  MALAR  BONE  is  rarely  fractured  alone  ; 
generally  it  is  driven  into  the  upper  jaw. 

THE  PAROTID  REGION.— The  main  part  of  the  PAROTID 
GLAND  lies  in  a  recess  bounded  in  front  by  the  ramus  of  the 
jaw,  with  the  masse ter  externally  and  the  internal  pterygoid 
internally ;  the  mastoid  process  and  the  sterno-mastoid 
muscle  behind  ;  the  temporo-maxillary  joint  and  external 
auditory  meatus  above  ;  and  a  horizontal  line  from  the  angle 
of  the  jaw  to  the  sterno-mastoid  below.  By  extending  the 
head  and  pushing  forward  the  lower  jaw  the  space  is  in- 
creased in  size,  while  by  opening  the  mouth  widely  the  upper 
portion  of  the  space  is  increased  by  gliding  forward  of  the 
condyle,  and  the  lower  portion  is  diminished.  The  gland  is 
enclosed  in  a  process  of  the  cervical  fascia,  which  splits  to 
enclose  it,  and  which  sends  in  numerous  septa,  subdividing 
the  gland.  The  superficial  layer  is  very  dense,  and  is  con- 
tinuous in  front  with  the  sheath  of  the  masseter  and  behind 
with  that  of  the  sterno-mastoid,  while  above  it  is  attached 
to  the  zygoma.  The  deep  layer  is  thin,  and  is  attached  above 
to  the  periosteum  of  the  auditory  meatus  and  glenoid  fossa, 


90  SURGICAL  ANATOMY 

and  forms  the  stylo-maxillary  ligament,  which  extends  from 
the  tip  of  the  styloid  process  to  the  posterior  surface  of  the 
angle  of  the  jaw,  between  the  insertions  of  the  masseter  and 
pterygoid  muscles.  The  deep  surface  of  the  gland  sheath 
is  related  to  the  posterior  belly  of  the  digastric  muscle,  the 
styloid  process  and  muscles  rising  from  it,  the  external  and 
internal  carotid  arteries'  and  internal  jugular  vein,  and  the 
ninth,  tenth,  eleventh,  and  twelfth  nerves.  The  gland 
generally  sends  several  processes  in  different  directions.  Thus 
a  facial  process  frequently  projects  forwards  toward  the  soda 
parotidis,  which  latter  lies  on  the  masseter  above  Stenson's 
duct ;  cervical  and  glenoid  processes  project  in  the  directions 
indicated  by  their  names  ;  while  a  pharyngeal  process  is  of 
importance,  as  it  passes  deeply  inwards  in  front  of  the  styloid 
process  and  above  the  stylo-maxillary  ligament  toward  the 
pharynx  and  tonsil.  Within  the  gland  are  numerous  structures, 
of  which  the  most  important  are  :  (a)  The  external  carotid 
artery,  which  enters  the  deep  surface  of  the  gland  at  the 
junction  of  the  middle  and  lower  third  of  the  posterior  border 
of  the  ascending  ramus  of  the  jaw,  passes  outwards  and  back- 
wards from  under  cover  of  the  ramus,  until,  on  reaching  the 
neck  of  the  condyle,  it  divides  into  the  internal  maxillary 
and  superficial  temporal  arteries,  (b)  The  facial  nerve, 
which,  after  leaving  the  stylo-mastoid  foramen,  immediately 
enters  the  gland  and  breaks  into  its  branches,  crossing  super- 
ficial to  the  external  carotid  artery.  The  temporo-maxillary 
vein,  the  occipital  and  posterior  auricular  branches  of  the 
external  carotid  artery,  and  small  branches  of  the  superficial 
temporal  and  internal  maxillary,  a  few  nerve  branches,  and 
lymphatic  glands  (draining  the  temporal,  scalp  region,  outer 
portion  of  the  eyelids,  posterior  part  of  the  cheek,  and  ear), 
are  also  present  in  the  gland. 

Owing  to  the  projecting  process  of  the  parotid  toward  the 
pharynx,  post-pharyngeal  abscesses  sometimes  find  their  way 
into  the  parotid  gland  ;  while,  on  the  other  hand,  owing  to  its 
dense  anterior  capsule,  suppurative  processes  in  the  parotid 
not  infrequently  extend  toward  the  pharynx.  In  other  cases 
parotid  abscesses  point  in  the  temporal  or  zygomatic  fossae 
or  in  the  neck,  while  sometimes  they  burst  into  the  meatus, 
or  even  find  their  way  along  the  divisions  of  the  fifth  nerve 
to  the  Gasserian  ganglion.  Parotid  abscesses  generally  arise 


THE  PAROTID  REGION  91 

from  septic  infection  conveyed  along  the  duct  from  the  mouth. 
Inflammatory  conditions  of  the  parotid  occasionally  supervene 
on  disease  or  injury  to  the  pelvic  viscera,  and  on  some  fevers, 
especially  typhoid,  while  the  affection  of  the  gland  called 
'  mumps  '  is  well  known.  Owing  to  the  tense  capsule,  all  of 
these  affections  are  very  painful,  the  auriculo-temporal  and 
great  auricular  nerves  being  pressed  on,  while,  where  the 
condition  is  not  relieved  by  operation,  sloughing  of  the  gland 
may  occur,  or  even  ulceration  of  one  of  the  large  vessels,  with 
consequent  severe  haemorrhage.  Movement  of  the  jaw  aggra- 
vates the  pain,  altering,  as  it  does,  the  size  and  shape  of  the 
space.  In  opening  a  parotid  abscess  care  is  necessary,  owing 
to  the  important  structures  contained.  A  horizontal  incision, 
as  low  as  possible,  so  as  to  avoid  Stenson's  duct  and  the  facial 
nerve,  is  generally  best,  and  then,  when  the  capsule  is  reached, 
it  is  penetrated  with  sinus  forceps  (Hilton).  Penetrating 
wounds  in  the  parotid  region  should  generally  be  treated  as 
serious,  owing  to  the  various  important  structures  which  may 
be  injured.  Bleeding  in  such  cases  is  frequently  very  severe, 
and  the  vessel  difficult  to  get  at.  Parotid  fistula  is  apt  to  result 
from  injury  to  the  gland  or  duct.  The  most  common  form  of 
TUMOUR  occurring  in  the  parotid  is  one  of  a  mixed  type,  and 
is  peculiar  in  that  it  generally  contains  cartilage  in  addition 
to  fibrous,  adenomatous,  and  myxomatous  tissue.  Some- 
times these  tumours  are  sarcomatous,  and  rapidly  infiltrate 
the  various  structures,  causing  limitation  of  movement  of  the 
jaw,  neuralgia,  and  later  anaesthesia  and  paralysis.  They  are 
generally  fixed,  so  that  they  cannot  be  moved  about  in  the 
gland  substance,  and  they  sometimes  perforate  the  external 
auditory  meatus.  Removal  is  difficult  or  impossible.  STEN- 
SON'S DUCT  begins  at  the  anterior  margin  of  the  gland  by  the 
junction  of  two  main  branches  proceeding  respectively  from 
the  upper  and  lower  segments,  and  runs  forwards  and  slightly 
downwards  to  the  anterior  margin  of  the  masseter,  where  it 
bends  nearly  at  right  angles,  pierces  the  fatty  tissue,  buc- 
cinator muscle,  and  mucous  membrane  of  the  cheek,  and  ends 
by  an. elliptical  orifice  on  the  level  of  the  second  upper  molar 
tooth.  It  is  about  2j  inches  long  and  J  inch  thick,  has  a 
firm  feel,  by  which  it  may  sometimes  be  detected  through  the 
skin,  lying  about  J  inch  below  the  zygoma,  and  its  course 
may  be  represented  by  a  line  drawn  from  the  lower  border 


92  SURGICAL  ANATOMY 

of  the  tragus  to  a  point  midway  between  the  nostril  and 
the  red  margin  of  the  lip.  In  its  course  it  is  accompanied 
by  the  transverse  facial  artery,  which  lies  above  it,  and  infra- 
orbital  branches  of  the  facial  nerve,  which  lie  above  or  below 
it.  Wounds  of  the  duct  are  very  apt  to  lead  to  salivary 
fistula,  which  are  treated,  where  practicable,  by  establishing 
an  opening  between  duct  and  mucous  membrane  on  the 
proximal  side  of  the  fistula.  Subcutaneous  rupture  of  the 
duct  leads  to  extravasation  of  saliva.  Where  the  duct  becomes 
blocked  by  calculus  a  painful  retention  cyst  is  apt  to  develop. 
In  passing  a  probe  it  is  best  to  evert  the  cheek  so  as  to 
straighten  the  duct. 

THE  LOWER  JAW.— Congenital  complete  absence  of  the 
lower  jaw  has  occurred  ;  also  partial  defects  and  incomplete 
development,  the  jaw  remaining  of  small  size.  Fracture 
occurs  most  commonly  at  or  near  the  mental  foramen,  the 
bone  being  weakened  by  the  foramen  and  the  fossa  foi  the 
canine  tooth.  It  is  practically  always  compound,  owing  to 
the  close  adherence  of  the  mucous  membrane  to  the  bone, 
but  the  displacement  is  generally  slight,  the  mylo-hyoid,  which 
is  attached  to  both  fragments,  modifying  the  displacement. 
As  a  rule,  therefore,  the  inferior  dental  nerve,  running  in  the 
interior  of  the  bone  through  the  inferior  dental  canal,  escapes 
severe  injury  at  the  time  of  the  accident,  though  it  may  become 
involved  in  callus  later.  The  tendency  toward  displacement, 
however,  is  for  the  anterior  fragment  to  be  drawn  downwards 
and  backwards  by  the  digastric,  mylo-  and  genio-hyoid,  and 
genio-hyo-glossus,  while  the  posterior  fragment  is  raised  by 
the  masseter,  internal  pterygoid,  and  temporal.  Fracture  of 
the  neck  of  the  condyle  occurs  occasionally  from  blows  on  the 
chin.  The  glenoid  fossa,  situated  in  front  of  the  osseous 
meatus  and  behind  the  eminentia  articularis  of  the  zygoma, 
which  separates  it  from  the  zygomatic  fossa,  is  divided  into 
an  anterior  articular  and  posterior  non-articular  portion  by 
the  Glaserian  fissure.  The  articular  portion  is  separated 
from  the  middle  fossa  of  the  skull  by  a  very  thin  plate  of  bone, 
and  cases  have  occurred  in  which  the  condyle  of  the  jaw  has 
been  driven  up  through  this  plate  into  the  cranial  cavity.  The 
condyle  of  the  jaw,  whose  long  axis  is  directed  inwards  and 
backwards,  is  separated  from  the  glenoid  by  an  interarticular 
fibro-cartilage,  on  either  surface  of  which  is  a  synovial  cavity. 


THE  LOWER  JAW  93 

The  cartilage  is  attached  to  the  capsule  and  to  the  condyle, 
with  which  it  moves  forwards  and  backwards  on  opening 
and  shutting  the  mouth.  It  sometimes  becomes  displaced 
forwards,  especially  in  delicate  women,  causing  a  subluxation 
of  the  jaw.  The  capsule  is  thin,  especially  in  front,  but  is 
strengthened  externally  by  the  external  lateral  ligament, 
which  is  directed  downwards  and  backwards  from  the  zygoma 
to  the  condyle.  The  accessory  ligaments  consist  of :  (a)  The 
spheno-maxillary  (internal  lateral),  from  the  spine  of  the 
sphenoid  to  the  ligula  and  ascending  ramus  of  the  jaw.  Be- 
tween it  and  the  neck  of  the  jaw  the  internal  maxillary  artery 
and  vein,  the  inferior  dental  vessels  and  nerve,  the  auriculo- 
temporal  nerve,  and  external  pterygoid  muscle,  are  situated. 
(b)  The  stylo-maxillary  (deep  parotid  fascia),  from  styloid 
process  to  angle  of  the  jaw.  (c)  The  pterygo-maxillary,  from 
hamular  process  of  sphenoid  to  base  of  ligula.  Dislocation 
of  the  jaw  is  nearly  always  forwards  through  the  weak  anterior 
portion  of  the  capsule,  and  is  said  to  be  more  frequently 
bilateral.  Dislocation  in  other  directions  is  generally  asso- 
ciated with  fracture.  The  forward  variety  occurs  when  the 
mouth  is  widely  open,  and  is  said  to  be  largely  due  to  the  action 
of  the  external  pterygoid  muscle,  which  draws  the  condyle 
forward  beyond  the  articular  eminence  into  the  zygomatic 
fossa  (the  articular  cartilage  remaining  behind),  where  it  is 
pulled  up  by  the  internal  pterygoid,  temporal,  and  masseter 
muscles.  In  reduction,  therefore,  it  is  first  necessary  to  depress 
the  condyle  before  pushing  it  backwards.  Suppurative  con- 
ditions may  extend  from  the  ear  or  parotid  gland  and  involve 
the  joint.  Abscesses  usually  point  at  the  front  of  the  joint, 
and  suppurative  processes  not  infrequently  lead  to  anchylosis. 
The  joint  is  frequently  affected  in  rheumatoid  arthritis,  giving 
rise  to  '  creaking  '  during  mastication  in  slight  cases  and 
excessive  movement  or  complete  anchylosis  in  severe  ones. 
In  such  cases  an  excision  of  the  condyle  through  a  curved 
incision  along  the  posterior  portion  of  the  upper  border  of  the 
zygoma  may  be  necessary.  Fixation  of  the  jaw  may  also 
arise  from  spasms  of  the  muscles  (trismus),  as  in  tetanus 
(risus  sardonicus),  and  sometimes  from  reflex  irritation  from 
the  lower  teeth  (caries  or  cutting  a  wisdom  tooth),  as  the  third 
division  of  the  fifth  nerve,  by  its  motor  root,  supplies  the 
muscles  of  mastication.  Dental  caries  has  also  been  known 


94  SURGICAL  ANATOMY 

to  cause  torticollis,  strabismus,  areas  of  hyperaesthesia, 
patches  of  grey  hair,  etc.,  through  reflex  action.  Tumours 
of  the  lower  jaw  frequently  arise  in  connection  with  the  teeth 
(dentigerous  cysts,  etc.)  Of  the  tumours  involving  the  jaw 
itself,  fibroma,  osteoma,  and  enchondroma  are  met  with,  and 
also  sarcoma.  The  latter  may  spring  from  the  periosteum, 
often  about  the  dental  margin  (malignant  epulis),  when  it  is 
generally  of  round  or  spindle-cell  type ;  or  it  may  be  of  the 
myeloid  type  and  originate  in  the  medulla  of  the  bone,  the 
bone  becoming  gradually  expanded,  while  the  patient  ex- 
periences progressive  toothache  as  the  various  dental  nerves 
become  involved.  In  such  cases  excision  of  half  of  the  lower 
jaw  may  be  necessary.  This  is  generally  performed  through 
an  incision  extending  through  the  lip  to  the  chin,  and  then 
carried  along  the  lower  border  of  the  jaw  and  superficially 
up  along  the  posterior  margin  of  the  ascending  ramus  to 
the  lobule  of  the  ear.  Unless  the  sarcoma  be  periosteal, 
a  subperiosteal  excision  of  the  half  jaw  is  next  performed, 
the  jaw  being  cut  through  near  the  symphysis  and  then  forcibly 
depressed,  when  the  insertion  of  the  temporal  muscle  into  the 
coronoid  process  is  cut  and  the  condyle  is  disarticulated  by 
a  twisting  movement,  the  capsule  and  external  pterygoid 
muscles  being  cut.  Reformation  of  the  bone  may  follow  such 
an  operation. 

The  blood-supply  of  the  lower  jaw  is  derived  from  the  facial 
(which  sends  a  submental  branch  along  the  inferior  border 
of  the  jaw  to  anastomose  with  the  mental  artery)  and  one  of 
the  terminal  branches  of  the  external  carotid,  the  internal 
maxillary,  which  sends  the  inferior  dental  artery  to  accompany 
the  nerve  of  that  name,  and  the  masseteric  to  the  masseter 
muscle.  The  nerve-supply  is  through  the  inferior  maxillary. 

TEETH. — The  time  of  eruption  of  the  MILK  TEETH  is 
variable.  The  lower  central  incisors  appear  about  the  sixth 
to  ninth  month,  upper  incisors  tenth  month,  lower  lateral 
incisors  and  first  four  molars  about  twelfth  to  fourteenth 
month.  Then  come  the  canines  and  four  second  molars,  the 
set  being  completed  by  the  end  of  the  second  year.  Of  the 
PERMANENT  TEETH  of  the  lower  jaw,  the  first  molars  appear 
about  the  sixth  year,  and  central  incisors  about  the  seventh, 
lateral  eighth,  first  premolars  ninth,  second  premolars  tenth, 
canines  eleventh,  second  molars  twelfth,  third  molars  about 


THE  TEETH  95 

seventeenth  year,  but  may  be  much  later  or  may  not  erupt. 
Those  of  the  upper  jaw  appear  a  little  later  than  those  of  the 
lower.  The  first  milk  tooth  is  cut  about  the  seventh  month, 
and  the  first  permanent  tooth  at  the  seventh  year.  The  milk 
teeth  are  twenty  in  number,  while  the  permanent  teeth  number 
thirty- two. 

A  tooth  is  formed  by  a  dipping  in  of  epithelium,  which 
becomes  cupped  at  its  extremity,  forming  the  enamel  organ, 
a  process  of  the  underlying  connective  tissue  growing  up  into 
it  and  forming  the  dentine  papilla.  The  tooth,  composed  of 
enamel  produced  by  the  enamel  organ,  and  of  dentine  by  the 
papilla  and  its  contained  cells  (odontoblasts),  is  contained  in 
a  tooth  sac  or  follicle  supplied  by  the  jaw  itself,  which  forms 
an  alveolar  periosteum  for  the  root,  which  is  partly  formed 
by  the  papilla  and  partly  by  the  deposit  of  cement  upon  it 
by  the  alveolar  periosteum.  The  remains  of  the  papilla  form 
the  pulp,  which  occupies  the  pulp  cavity. 

As  the  permanent  teeth  approach  the  surface,  the  milk 
teeth  generally  fall  out,  owing  to  absorption  of  their  roots. 

The  upper  incisors  and  canines  and  the  lower  bicusps 
have  cylindrical  roots,  and  hence  in  extracting  are  first 
loosened  by  a  rotatory  movement.  The  roots  of  the  lower 
incisors  and  canines  and  the  upper  bicusps  are  flattened, 
necessitating  a  lateral  movement  to  loosen  them.  The  roots 
of  the  upper  molars  are  three  in  number,  whereas  those  of  the 
lower  molars  are  two,  and  the  roots  of  the  two  first  upper 
molars  are  frequently  divergent,  while  those  of  the  wisdom 
teeth  of  both  jaws,  but  particularly  the  lower,  are  convergent 
and  curved  backwards.  After  extraction  of  a  permanent  tooth, 
absorption  of  the  alveolar  margin  of  the  jaw  generally  occurs. 

Alveolar  abscess  frequently  occurs  in  connection  with  the 
fangs  of  the  teeth.  Where  the  tooth  has  a  single  fang  the  pus 
may  travel  along  the  fang  to  the  surface,  but  in  other  teeth  it 
tends  rather  to  burrow  through  the  alveolus,  pointing  in  some 
cases  through  the  gum,  but  more  generally  through  the  cheek. 

The  chief  forms  of  tooth  tumours  are  odontomes,  which 
occur  during  the  developmental  period,  and  consist  of  dental 
tissue,  and  dentigerous  cysts,  which  consist  of  an  expansion  of 
the  follicle  of  an  unerupted  tooth,  which  is  found  generally 
within  the  cyst. 

Hereditary   syphilis   affects   chiefly   the    permanent   upper 


96 


SURGICAL  ANATOMY 


central  incisors,  which,  instead  of  presenting  a  narrow  neck 
and  broad  crown,  have  a  broad  base  and  taper  toward  the 
crown  (peg-shaped),  which  is  frequently  notched  ('  Hutchinson 
teeth  '). 

81         32  1 


FIG.   10. — THE  ZYGOMATIC  AND 
(From  Buchanan's 

1.  Great  wing  of  sphenoid.  17. 

2.  Spheno-maxillary  fissure.  18. 

3.  Back  part  of  infra-orb,  groove.  19. 

4.  Spheno-maxillary  fossa.  20. 

5.  Infratemporal  crest.  21. 

6.  Spheno-palat.  foramen.  22. 

7.  Zygom.  surf,  of  great  wing  of  sphenoid.      23. 

8.  Pterygo-maxillary  fissure.  24. 

9.  Zygoma.  25. 

10.  Preglenoid  tubercle.  26. 

11.  Foramen  ovale.  27. 

12.  Foramen  spinosum.  28. 

13.  Spine  of  sphenoid.  29. 

14.  Openings  of  posterior  dental  canals.  30. 

15.  External  pterygoid  plate  of  sphenoid.  31. 

16.  Hamular  process.  32. 


SPHENO-MAXILLARY 
"  Anatomy.") 

Tuberosity  of  palate  bone. 

Tuberosity  of  superior  maxilla. 

Canine  fossa. 

Incisor  fossa. 

Anterior  nasal  spine. 

Nasal  notch. 

Malar  foramen. 

Orbital  surface  of  lachrymal  bone. 

Lachrymal  groove. 

Nasal  plate  of  superior  maxilla. 

Nasal  bone. 

Fronto-maxillary  suture. 

Fronto-nasal  suture. 

GlabeUa. 

Orbital  plate  of  frontal. 

Fronto-malar  suture. 


The  PTERYGO-MAXILLARY  OR  ZYGOMATIC  FOSSA  is  a 

comparatively  small  space,  bounded  anteriorly  by  the  zygo- 
matic  surface  of  the  superior  maxilla  ;  internally  by  the 
external  pterygoid  plate  and  pterygo-spinous  ligament,  which 


ZYGOMAT1C  FOSSA  97 

frequently  ossifies  ;  posteriorly  by  a  line  from  the  foramen 
spinosum  to  the  tubercle  of  the  zygoma  ;  and  externally  by 
the  zygomatic  arch  and  ramus  of  the  inferior  maxilla.  Above 
it  is  partially  bounded  by  the  great  wing  of  the  sphenoid  and 
a  small  portion  of  the  squamous  of  the  temporal,  and  it  is 
quite  open  below.  It  communicates  anteriorly  with  the  spheno- 
maxillary  fossa  by  the  ptery go-maxillary  fissure  (which  is  a 
vertical  fissure  between  the  superior  maxilla  and  the  external 
pterygoid  plate),  and  with  the  orbit  by  the  spheno-maxillary 
fissure  (which  is  a  horizontal  fissure  running  at  right  angles 
to  the  pterygo-maxillary,  separating  the  great  wing  of  the 
sphenoid  from  the  orbital  margin  of  the  maxilla) .  Above  it  is 
continuous  with  the  temporal  fossa  beneath  the  zygoma,  and 
below  with  the  parotid  region.  Indirectly  the  space  is  con- 
tinuous with  the  nasal  fossa  through  the  spheno-palatine 
foramen  (from  spheno-maxillary  to  nasal  fossa),  and  with  the 
cranial  cavity  through  the  sphenoidal  fissure  (from  cranial 
cavity  to  orbit),  and  thus  siippurative  processes  may  find  their 
way  through  it  to  or  from  the  nasal,  orbital,  temporal,  parotid, 
or  cranial  regions.  Zygomatic  abscess  may  point  on  the  face, 
neck,  or  in  the  pharynx.  The  pterygo-maxillary  fossa  is 
occupied  by  the  two  pterygoid  muscles  and  a  small  portion 
of  the  temporal,  the  internal  maxillary  artery  and  branches, 
the  pterygoid  venous  plexus,  and  the  third  division  of  the  fifth 
nerve. 

The  temporal  muscle,  which  is  inserted  into  the  coronoid 
process  of  the  lower  jaw,  is  situated  chiefly  in  the  temporal 
fossa,  and  is  covered  externally  by  a  dense  fascia,  the  temporal 
fascia.  This  fascia  is  continuous  above  with  the  occipito- 
frontalis  aponeurosis,  which  is  attached  along  the  temporal 
crest  and  covers  the  muscle  as  far  as  the  zygoma,  to  which 
it  is  attached  in  two  layers,  a  quantity  of  fat  intervening 
between  them.  This  fascia  is  very  dense,  and,  like  the  occipito- 
frontalis  aponeurosis,  may,  when  cut  through,  give  the 
sensation  of  broken  bone  to  the  examining  finger.  Anteriorly 
the  deep  fascia  loses  itself  on  the  face,  and  posteriorly  it  forms 
the  thin  masseteric  fascia  and  the  thicker  parotid  capsule. 
Lying  behind  the  temporal  fascia  and  muscle  is  a  quantity 
of  fat,  continuous  with  that  in  the  pterygo-maxillary  fossa, 
the  absorption  of  which  produces  the  prominent  malar  bone 
and  zygoma  seen  in  extreme  emaciation.  Fracture  of  the 

7 


g8  SURGICAL  ANATOMY 

zygoma  may  be  due  to  direct  or  indirect  violence.  There  is 
generally  little  displacement,  owing  to  the  attachment  of  the 
temporal  fascia  above  and  masseter  muscle  below,  but  a 
fragment  may  be  detached  and  driven  into  the  temporal 
muscle,  and  cause  pain  on  mastication.  Abscesses  in  the 
temporal  fossa  tend  to  point  in  the  pterygo-maxillary  region 
or  in  the  neck.  The  external  pterygoid  muscle  runs  backwards 
from  its  origins  from  the  great  wing  of  the  sphenoid  and 
external  pterygoid  plate,  to  be  inserted  into  the  neck  of  the 
lower  jaw  and  the  interarticular  fibre-cartilage,  and  has  the 
internal  maxillary  artery  on  its  outer  side,  as  a  rule,  while  the 
branches  of  the  third  division  of  the  fifth  nerve  surround  it. 
The  internal  maxillary  artery  gives  off  the  middle  meningeal 
artery,  which  ascends  through  the  foramen  spinosum,  at  which 
point  it  is  sometimes  caught  in  fracture  of  the  skull,  and  the 
inferior  dental,  which  enters  the  inferior  dental  canal,  and 
numerous  muscular  and  other  branches. 

The  pterygoid  venous  plexus  is  situated  chiefly  beneath  the 
upper  origin  of  the  external  pterygoid,  its  blood  being  removed 
by  the  internal  maxillary  vein.  It  forms  a  venous  communica- 
tion between  nose,  orbit,  and  cranium,  including  the  cavernous 
sinus.  The  internal  pterygoid  muscle,  arising  from  the  deep 
surface  of  the  external  pterygoid  plate  and  from  the  tuberosity 
of  the  upper  jaw,  is  quadrilateral  in  form,  and  is  directed 
downwards  and  backwards  on  the  deep  surface  of  the  external 
pterygoid  to  the  inner  surface  of  the  lower  jaw  near  the 
angle. 

The  third  division  of  the  fifth  nerve  is  joined  by  the  motor 
root  immediately  after  its  exit  from  the  foramen  ovale.  At 
this  point  it  lies  on  the  deep  surface  of  the  external  pterygoid, 
and  then  breaks  into  two  divisions,  an  anterior,  which  is  almost 
entirely  motor,  and  supplies  the  muscles  of  mastication, 
excepting  the  buccinator  (which  is  supplied  by  the  facial), 
and  a  posterior  sensory,  which  gives  off  the  auriculo-temporal 
nerve  to  the  parotid  gland,  ear,  etc. ;  the  inferior  dental,  which 
supplies  the  teeth,  and  gives  off  a  mental  branch ;  and  the 
lingual,  which  crosses  between  the  ramus  of  the  jaw  and 
external  pterygoid  to  the  tongue,  sublingual  and  submaxillary 
glands.  While  it  supplies  the  tongue  with  sensation,  it  also 
has  some  taste  fibres  derived  from  the  chorda  tympani.  The 
inferior  dental  nerve  is  sometimes  divided  for  neuralgia,  being 


SPHENO-M AXILLARY  FOSSA  99 

reached  .either  through  the  mouth  by  a  vertical  incision  along 
the  inner  side  of  the  ascending  ramus  of  the  jaw  or  by  tre- 
phining through  the  central  point  of  the  ascending  ramus,  and 
so  reaching  the  nerve  as  it  enters  the  canal.  The  lingual 
nerve  is  sometimes  sectioned  for  the  relief  of  pain  and  salivation 
in  carcinoma  linguae.  It  may  be  reached  through  the  mouth 
by  an  incision  J  inch  below  and  behind  the  last  molar  tooth, 
or  through  the  neck  by  an  incision  similar  to  that  for  ligature 
of  the  lingual  artery,  after  which  the  capsule  of  the  sub- 
maxillary  gland  is  divided,  the  gland  turned  up,  and  the  nerve 
found  at  the  point  at  which  it  is  connected  with  the  sub- 
maxillary  ganglion.  The  inferior  maxillary  trunk,  and  also 
the  Gasserian  ganglion,  have  been  attacked  through  the 
pterygo-maxillary  space.  The  zygoma  is  cut  and  turned 
down  with  the  masseter,  the  coronoid  process  is  cut  and 
turned  up  with  the  temporal,  and  the  external  pterygoid  is 
shelled  from  its  attachments.  If  the  Gasserian  ganglion  is 
to  be  attacked  (Rose's  operation),  it  is  further  necessary  to 
trephine  the  skull  close  to  the  foramen  ovale.  In  these 
operations  haemorrhage  from  the  internal  maxillary  artery 
and  pterygoid  venous  plexus  is  generally  very  great,  fre- 
quently necessitating  postponement  of  the  complete  opera- 
tion, and  even  ligature  of  the  common  carotid.  The  Gas- 
serian ganglion  has  also  been  attacked  by  turning  down  a 
large  flap  of  bone  from  the  temporal  region  (Hartley- Krause 
method),  but  here  also  the  haemorrhage  is  generally  very  great. 
Attention  has  already  been  drawn  to  the  method  of  attacking 
the  ganglion  through  an  incision  in  the  face  (p.  13). 

The  SPHENO-MAXILLARY  FOSSA  is  a  small  triangular 
space  situated  beneath  the  apex  of  the  orbital  cavity  at  the 
angle  of  junction  of  the  spheno-maxillary  and  pterygo-max- 
illary fissures,  which  communicates  with  the  orbit  by  the 
former,  with  the  zygomatic  fossa  by  the  latter,  and  with 
the  nasal  fossae  by  the  spheno-palatine  foramen. 

It  is  bounded  above  by  the  body  of  the  sphenoid  and  orbital 
process  of  the  palate  bone  ;  in  front  by  the  superior  maxilla  ; 
behind  by  the  base  of  the  pterygoid  process  and  great  wing 
of  the  sphenoid  ;  and  internally  by  the  vertical  plate  of  the 
palate.  Three  foramina  open  on  its  posterior  wall — foramen 
rotundum  above,  Vidian  canal  below,  and  pterygo-palatine 
canal  below  and  internal.  Two  foramina  open  on  the  inner 

7—2 


loo  SURGICAL  ANATOMY 

wall — spheno-palatine    above    and    posterior   palatine    canal 
below. 

The  CAVITY  OF  THE  MOUTH  is  described  as  consisting 
of  two  parts,  an  anterior,  or  vestibule,  and  a  posterior,  the 
mouth  proper,  or  buccal  cavity,  which  are  separated  from  one 
another  by  the  gums  and  teeth.  When  the  mouth  is  tightly 
shut,  the  only  available  opening  between  the  two,  if  the  teeth 
be  intact,  is  behind  the  last  molar  tooth.  Through  this 
interval  between  the  last  molar  and  the  ascending  ramus  of 
the  jaw  patients  affected  with  tetanus  are  frequently  fed  by 
a  tube,  and  a  similar  mode  is  frequently  adopted  in  cases  of 
fracture  of  the  lower  jaw.  The  lips  are  very  mobile,  the 
mobility  rendering  them  liable  to  contraction  deformity,  and 
they  are  composed  from  without  inwards  of  skin,  superficial 
fascia,  orbicularis  oris,  submucous  tissue  containing  many 
mucous  glands,  and  the  coronary  branches  from  the  facial 
artery  and  mucous  membrane.  Thus  the  vessels  are  close  to 
the  inside  of  the  lip,  and  may  be  wounded  against  the  teeth, 
and,  as  they  possess  a  free  anastomosis,  considerable  bleeding 
may  result,  the  blood  frequently  being  swallowed  and  sub- 
sequently vomited,  causing  internal  injuries  to  be  suspected. 
The  mucous  membrane  of  the  lips  rests  on  a  loose  subcutaneous 
tissue,  which  readily  becomes  infiltrated  in  inflammatory 
affections,  causing  considerable  swelling.  The  glands  in  the 
submucous  tissue  are  numerous,  and  their  ducts,  when 
blocked,  may  give  rise  to  mucous  cysts,  which  occasionally 
attain  a  large  size,  while  a  general  hypertrophy  of  the  glands 
may  cause  a  uniform  enlargement  of  the  lip.  Nczvi  frequently 
occur  on  the  lips,  and  the  lower  lip  is  the  most  frequent  seat 
of  epithelioma.  As  the  lymphatics  of  both  lips  drain  to  the 
submaxillary  glands,  it  is  there  that  evidence  of  secondary 
extension  should  first  be  sought.  A  congenital  enlargement 
of  the  lip  due  to  lymphatic  hypertrophy  is  rarely  met  with, 
and  is  called  macrocheilia.  The  upper  lip  derives  its  sensation 
from  the  second  and  the  lower  from  the  third  division  of  the 
fifth  nerve,  labial  herpes  frequently  occurring  over  the  distribu- 
tion of  these  nerves  in  cases  of  fever,  gastric  disturbance,  etc. 
Stenson's  duct  opens  on  the  mucous  membrane  of  the  cheek 
opposite  the  second  upper  molar  tooth,  and  as  it  bends  almost 
at  a  right  angle  just  prior  to  opening,  it  is  necessary,  when 
passing  a  probe  along  it,  to  evert  the  cheek  in  order  to  remove 


THE  MOUTH  101 

the  bend.  The  ptery  go -maxillary  ligament  can  be  seen 
running  from  above  downwards  toward  the  last  molar  tooth, 
when  the  mouth  is  widely  open.  The  lingual  or  gustatory 
nerve  lies  just  in  front  of  this,  below  the  last  molar  tooth  and 
close  to  the  bone,  where  it  has  been  injured  by  slipping  of  the 
forceps  in  extraction  of  the  last  molar. 

Normally  the  lips  and  cheeks  press  against  the  teeth  and 
gums,  thus  rendering  the  cavity  of  the  vestibule  only  potential. 
In  facial  paralysis,  on  the  other  hand,  the  lips  and  cheeks 
fall  away  from  the  teeth,  permitting  the  accumulation  of  food 
in  the  vestibule,  while,  owing  to  the  inability  to  close  the  lips 
firmly,  fluid  is  generally  permitted  to  run  out  at  the  side  of 
the  mouth. 

Hare-lip  is  a  uni-  or  bi-lateral  defect  in  the  upper  lip, 
varying  from  a  slight  notch  in  the  margin  of  the  lip  to  a  gap 
extending  into  the  nostril,  due  to  imperfect  fusion  between 
the  fronto-nasal  and  superior  maxillary  processes.  A  con- 
tinuation of  the  defect  by  the  side  of  the  nose  upwards  to 
the  lower  eyelid,  which  may  be  involved,  is  called  a  coloboma 
jacialis. 

A  median  hare-lip  is  rare.  In  the  upper  lip  it  is  due  to 
persistence  of  a  little  cleft  at  the  extremity  of  the  fronto-nasal 
process  (globular  process),  and  in  the  lower  lip  to  failure  of 
fusion  of  the  two  mandibular  processes. 

Macrostoma,  a  lateral  continuation  of  the  aperture  of  the 
mouth,  is  due  to  imperfect  fusion  between  the  maxillary  and 
mandibular  processes,  while  microstoma  is  due  to  excessive 
fusion. 

The  gums  are  normally  firm  and  vascular.  They  are  fre- 
quently affected  in  scurvy  and  in  mercurial  and  chronic  lead- 
poisoning,  a  blue  line  forming  at  the  junction  of  teeth  and 
gum  in  the  latter  affection,  especially  if  the  mouth  be  not 
kept  clean.  The  mucous  membrane  covering  the  gums  is  thin 
and  adherent,  save  at  the  reflections,  and  is  generally  torn 
through  in  fracture  of  the  lower  jaw. 

The  buccal  cavity  communicates  anteriorly  with  the  vesti- 
bule, as  already  described,  and  posteriorly,  through  the 
isthmus  of  the  fauces,  with  the  pharynx.  It  contains  the 
tongue,  and  presents  the  openings  of  several  salivary  ducts. 
When  the  mouth  is  shut,  and  breathing  is  conducted  through 
the  nose,  the  tongue  practically  fills  the  whole  cavity,  render- 


102  SURGICAL  ANATOMY 

ing  it,  like  the  vestibule,  potential.  Wharton's  duct  from  the 
submaxillary  gland  opens  on  a  soft  papilla  on  the  under 
surface  of  the  tongue,  at  its  base  and  close  to  the  middle  line. 
A  ridge,  the  plica  sublingualis,  runs  outwards  and  backwards 
from  this  point  on  either  side.  It  is  caused  by  the  underlying 
sublingual  gland,  the  numerous  ducts  from  which  (ducts  of 
Rivini]  open  near  the  crest  of  the  ridge.  Rarely  a  large 
duct  (Bartholin's)  comes  from  the  sublingual  gland  and  opens 
close  to  or  along  with  Wharton's  duct.  Wharton's  duct  is 
indistensible,  and,  when  blocked  by  a  calculus,  causes  con- 
siderable pain.  Ranula,  a  mucous  cyst  found  on  the  floor  of 
the  mouth,  may  be  due  to  dilatation  of  Wharton's  duct  or  of 
one  of  the  sublingual  ducts,  or  to  occlusion  of  one  of  the 
mucous  follicles  which  are  numerous  under  the  tongue. 

Dermoids,  due  to  persistence  of  the  upper  end  of  the  thyro- 
glossal  duct,  sometimes  occur  on  the  floor  of  the  mouth.  An 
acute  form  of  submaxillary  cellulitis,  called  Ludwig's  angina, 
sometimes  occurs,  involving  both  sides  of  the  floor  of  the 
mouth,  causing  great  swelling,  which  pushes  the  tongue  up- 
wards and  backwards,  and  giving  rise  to  danger  from  sloughing, 
haemorrhage,  pyaemia,  and  even  asphyxia  when  the  larynx 
is  involved.  It  is  best  treated  by  median  external  incision 
between  the  chin  and  hyoid,  and  Hilton's  method  of  opening 
may  often  be  employed  with  advantage. 

The  tongue  is  almost  entirely  a  muscular  organ,  which  has 
the  hyoid  bone  as  a  point  of  attachment,  both  for  several  of 
its  muscles  and  for  the  hyo-glossal  ligament.  It  plays  an 
important  part  in  mastication,  keeping  the  food  between  the 
teeth  with  the  help  of  the  lips  and  cheeks,  and  in  swallowing, 
in  which  act  it  guides  the  food  backwards,  and,  pushing  down 
the  epiglottis,  to  which  three  folds  of  mucous  membrane  run 
(glosso-epiglottidean  folds),  covers  over  the  upper  end  of  the 
trachea.  It  is  curious  to  note  that  the  soft  yielding  tongue 
is  a  potent  factor  in  moulding  the  rigid  jaw,  which  latter,  after 
excision  of  the  tongue,  frequently  falls  in.  While  the  tongue 
certainly  plays  an  important  part  in  speech,  it  is  by  no  means 
essential  for  that  purpose,  patients  frequently  being  able  to 
speak  excellently  after  excision  of  the  tongue,  and  even 
swallowing  is  managed  with  practically  no  difficulty.  The 
mucous  membrane  of  the  tongue  presents  on  the  dorsum 
anteriorly  a  large  number  of  filiform  and  a  less  number  of 


THE  TONGUE  103 

fungifocm  papillae,  and  posteriorly  a  row  of  circumvallate 
papillae  arranged  in  a  V-shape,  with  the  apex  directed  back- 
wards. The  foramen  ccecum  is  situated  at  the  apex,  while  the 
limbs  stretch  out  and  forwards  toward  the  anterior  palatine 
arches.  Behind  the  circumvallate  papillae  it  is  smooth  but 
nodular,  owing  to  the  presence  of  the  lingual  tonsil  beneath 
the  surface.  This  posterior  third  of  the  tongue  is  almost 
vertical,  and  forms  the  anterior  wall  of  the  oral  pharynx. 
When  swollen,  it  may  interfere  with  the  action  of  the  epiglottis, 
to  which  it  is  connected  by  a  median  fold  of  mucous  mem- 
brane, the  frenulum  epiglottidis.  The  mucous  membrane  of 
this  region  is  continuous  laterally  with  that  of  the  tonsils 
and  pharynx.  In  many  debilitated  conditions  the  surface 
epithelium  of  the  tongue  accumulates  and  becomes  sodden 
and  stained,  producing  a  furred  tongue  ;  while  the  strawberry 
tongue  of  scarlet  fever  is  due  to  the  bright  red  colour  of  the 
sparse  fungiform  papillae  scattered  throughout  the  fur.  While 
the  surface  normally  is  fairly  smooth,  save  for  the  median 
raphe,  it  becomes  much  fissured  in  syphilis  of  the  tongue,  and 
is  frequently  associated  with  leucoplakia,  in  which  the  villi 
are  generally  destroyed  and  the  epithelium  becomes  thick 
and  white,  resembling  white  oil-paint.  The  foramen  caecum 
is  a  remnant  of  the  thyro-glossal  duct,  from  which  cystic 
tumours,  some  of  which  are  malignant,  and  dermoids  have 
developed.  The  latter  have  occasionally  been  so  large  as  to 
protrude  the  tongue  from  the  mouth. 

The  UNDER  SURFACE  of  the  tongue  is  covered  with  smooth, 
comparatively  lax  mucous  membrane,  and  presents  a  median 
fold  of  mucous  membrane,  the  frenulum  lingua,  which  extends 
from  it  to  the  floor  of  the  mouth  toward  the  lower  jaw.  This 
frenulum  is  sometimes  very  short,  giving  rise  to  the  condition 
known  as  '  tongue-tie,'  which,  when  pronounced,  may  cause  the 
infant  difficulty  in  sucking.  If  it  be  necessary  to  cut  it.  this 
should  be  done  with  care  close  to  the  jaw,  as  a  free  incision 
may  wound  the  ranine  vessels,  and  even  permit  the  tongue 
to  turn  over  into  the  pharynx.  On  either  side  of  the  frenulum 
the  ranine  vein  may  be  seen,  lying  near  the  surface,  while  the 
arteries  run  somewhat  parallel,  but  much  more  deeply.  The 
tongue  is  richly  supplied  with  blood,  and  is  a  frequent  seat  of 
ncevi.  In  addition  to  the  lingual  vessels  (which  send  off 
a  dorsal  branch  proximal  to  the  usual  place  of  ligature  in  the 


104  SURGICAL  ANATOMY 

neck,  which  supplies  the  root  of  the  tongue  and  the  tonsil),  it 
receives  blood  by  anastomosis  with  small  branches  of  the 
ascending  pharyngeal  and  facial  arteries.  The  tongue  pos- 
sesses a  rich  lymphatic  supply,  the  channels  from  the  posterior 
half  following  the  ranine  vein  to  discharge  into  the  deep 
cervical  glands  beneath  the  sterno-mastoid  and  angle  of  the 
jaw,  while  those  from  the  anterior  portion  (that  most  fre- 
quently affected  by  carcinoma)  pass  through  the  mylo-hyoid 
muscle  into  the  submaxillary  glands.  A  great  increase  in  the 
lymphatics,  occurring  congenitally,  is  known  as  macroglossia. 
It  is  a  rare  condition,  and  the  tongue  has  become  so  much 
enlarged  in  such  cases  as  to  protrude  several  inches  from  the 
mouth,  and  even  cause  dislocation  of  the  jaw.  The  tongue 
is  occasionally  affected  by  parenchymatous  glossitis,  in  which 
it  becomes  greatly  swollen,  possibly  protruding  between  the 
teeth,  and  tending  to  cause  suffocation  by  backward  pressure 
and  oedema  of  the  aryteno-epiglottic  folds. 

The  nerve- supply  of  the  tongue  is  rather  complex.  The 
twelfth  is  the  motor  nerve,  supplying  all  the  muscles  (except  the 
palato-glossus,  which  is  supplied  by  the  pharyngeal  plexus). 
This  nerve  leaves  the  skull  by  the  anterior  condylar  foramen, 
at  which  point  it  has  been  damaged  by  injury  to  the  back  of  the 
head,  giving  rise  to  atrophy  of  half  of  the  tongue.  The  lingual 
(fifth)  supplies  the  anterior  two-thirds  of  the  tongue  with 
common  sensation,  and  tactile  sensation  is  more  sensitive  at 
the  tip  of  the  tongue  than  in  any  other  part  of  the  body. 
In  painful  affections  of  the  anterior  portion  of  the  tongue 
pain  is  frequently  referred  to  the  auditory  meatus  and  skin 
of  the  surrounding  parts  (supplied  by  the  auriculo-temporal 
branch  of  the  fifth).  The  lingual  may  also  supply  taste  to 
this  portion,  but  it  is  more  probably  due  to  the  chorda  tympani 
(given  off  by  the  facial  in  the  aqueduct  of  Fallopius),  and  in 
support  of  this  view  is  the  fact  that  the  destruction  of  the 
chorda  in  the  aqueduct  has  been  followed  by  loss  of  taste  in 
the  tongue  on  that  side,  while  stimulation  caused  sensations 
of  taste.  The  chorda  has  also  an  effect  on  nutrition  of  the 
tongue  (including  the  circumvallate  papillae).  The  epiglottis 
and  base  of  the  tongue  are  partially  enervated  by  the  internal 
laryngeal  (of  tenth). 

The  muscles  of  the  tongue  may  be  considered  in  three  groups 
— intrinsic,  extrinsic,  and  accessory.  The  intrinsic  are  com- 


THE  TONGUE  105 

posed  orf  a  cortical  layer  of  longitudinal  fibres  (with  which  the 
hyo-  and  stylo-glossi  blend)  and  a  central  core  of  transverse 
and  vertical  fibres  (with  which  fibres  of  the  genio-glossi  blend) , 
which  are  divided  into  two  lateral  masses  by  the  septum. 
The  extrinsic  consist  of  the  hyo-,  genio-hyo-,  stylo-,  and 
palato-glossi  muscles,  which  largely  compose  the  root  of  the 
tongue.  The  accessory  consist  of  the  muscles  which  act 
indirectly  on  the  tongue  through  the  hyoid  bone — omo-, 
mylo-,  genio-,  stylo-,  and  sterno-hyoid,  and  digastric. 

Unilateral  paralysis  of  the  tongue  results  in  deflection 
to  the  affected  side  when  the  organ  is  protruded.  Complete 
paralysis  of  the  tongue,  which  is  generally  due  to  a  central 
lesion,  produces  rapid  atrophy  and  difficulty  in  swallow- 
ing. In  the  second  stage  of  anesthesia  the  tongue  frequently 
tends  to  fall  back,  pushing  down  the  epiglottis  over  the 
'trachea.  In  such  cases  pushing  forward  the  angle  of  the 
jaw  is  frequently  effective,  acting,  as  it  does,  on  the  extrinsic 
and  accessory  muscles  of  the  tongue. 

In  addition  to  simple  pyogenic  ULCERS,  which  occur  on  the 
mucous  membrane  of  the  tongue  and  lips,  the  tongue  is  affected 
by  tubercular,  syphilitic,  and  carcinomatous  ulcers.  The 
syphilitic  ulcers  generalty  affect  the  dorsum,  and  can  be 
comparatively  easily  differentiated,  whereas  tubercular  and 
epitheliomatous  ulcers  generally  affect  the  margin,  are  not 
always  easy  of  differentiation,  and  generally  demand  excision 
of  the  tongue.  Tubercular  ulcers,  however,  are  not  so  com- 
mon as  carcinomatous,  and  affect  generally  younger  subjects. 
As  a  carcinomatous  growth  increases  in  size  it  tends  to  spread 
to  the  floor  of  the  mouth,  tonsil,  etc.  Pain  over  the  anterior 
two-thirds,  supplied  by  the  lingual  nerve,  and  salivation  are 
generally  pronounced  in  advanced  cases,  and  to  relieve  these 
section  of  the  lingual  nerve  has  been  done.  Hemorrhage, 
also,  is  sometimes  serious.  In  EXCISING  THE  TONGUE  it  is 
generally  well  to  begin  by  ligaturing  both  lingual  arteries  in 
the  neck,  and,  at  the  same  time,  to  remove  the  submaxillary 
salivary  gland  on  the  affected  side,  as  it  contains  numerous 
lymphatic  glands,  which  are  generally  involved  at  an  early 
stage,  and  any  other  lymphatic  glands  in  the  submaxillary 
region,  while,  if  necessary,  by  prolonging  the  posterior  end  of 
the  wound  upwards  and  backwards,  the  internal  jugular  and 
the  glands  surrounding  it  may  be  exposed.  The  facial  artery 


io6  SURGICAL  ANATOMY 

is  almost  necessarily  cut  if  this  be  done.  The  mylo-hyoid 
muscles  may  next  be  cut  through,  and  then  the  mucous 
membrane  of  the  floor  of  the  mouth,  taking  care  to  cut  it 
close  to  the  jaw  on  the  diseased  side.  The  two  wounds 
in  the  neck  are  then  packed  with  iodoform  gauze.  The 
tongue  can  now  be  drawn  well  forward  in  the  mouth,  and 
divided  as  far  back  as  possible,  care  being  taken  to  pass  a 
stitch  through  the  stump  to  prevent  its  falling  back  upon  the 
epiglottis,  and,  with  the  same  end  in  view,  it  is  generally 
desirable  to  leave  the  genio-hyoids  and  genio-hyo-glossi 
intact  on  at  least  one  side.  The  tongue  has  also  been  removed, 
after  dividing  the  lower  jaw,  and  by  cutting  out  from  the 
mouth  by  ecraseur,  or  scissors,  withbut  previous  ligature  of 
the  lingual. 

The  palate  separates  the  buccal  from  the  nasal  cavities,  and 
consists  of  two  parts — hard  and  soft.  The  hard  palate  is 
formed  by  the  palatal  processes  of  the  superior  maxillary  and 
palate  bones,  which  present  at  their  junction  in  the  middle 
line  the  palatal  crest,  while  the  premaxillary  bone  forms  the 
portion  in  the  centre,  anterior  to  the  anterior  palatine  canal, 
which  bears  the  upper  incisor  teeth.  The  anterior  palatine 
canal  transmits  the  naso-palatine  nerves.  The  HARD  PALATE 
becomes  thinner  posteriorly,  and  presents  the  posterior  nasal 
spine  projecting  backwards  from  it.  The  posterior  palatine 
canal,  which  transmits  the  vessels  of  that  name  (from  internal 
maxillary),  and  the  anterior  palatine  nerve  (from  Meckel's 
ganglion),  is  situated  at  the  postero-external  angle  of  the 
hard  palate  just  inside  the  alveolus  of  the  wisdom  tooth.  The 
hard  palate  is  covered  by  a  firm  muco-periosteum,  bound 
together  by  a  quantity  of  connective  tissue,  which  contains 
numerous  mucous  glands.  It  is  nourished  by  the  posterior 
palatine  vessels,  which  run  forward  close  to  the  bone  to  the. 
anterior  palatine  foramen.  The  arch  of  the  palate  varies 
considerably  in  different  individuals,  and  is  said  to  be  very 
high  in  congenital  idiots.  The  SOFT  PALATE  is  continued 
backwards  from  the  posterior  end  of  the  hard  palate,  and 
consists  anteriorly  of  a  firm  aponeurosis  covered  by  mucous 
membrane,  while  posteriorly  it  contains  muscles,  etc.,  and  is 
very  movable.  Its  posterior  free  border  presents  two  arches, 
folds  of  mucous  membrane — the  pillars  of  the  fauces — on 
either  side  surrounding  the  isthmus  of  the  fauces  or  entrance 


THE  PALATE  107 

to  theypharynx.  The  anterior  pillar  contains  the  palato- 
glossi  muscles  and  fuses  with  the  dorsal  aspect  of  the  tongue, 
and  the  posterior  contains  the  palato-pharyngei  muscles  and 
fuses  with  the  pharyngeal  wall.  Between  the  pillars  of  the 
fauces  the  tonsils  aie  lodged.  Where  the  soft  palate  is  cleft, 
the  cleft  is  narrowed  in  swallowing  by  the  superior  constrictor. 
The  levator  palati  and  tensor  palati  muscles,  on  the  other 
hand,  arise  near  together  from  the  Eustachian  tube,  and  tend 
to  widen  it.  The  former  passes  down  and  inwards  into  the 
palate,  while  the  latter  descends  to  the  hamular  process  (which 
is  situated  behind  and  to  the  inner  side  of  the  wisdom  tooth), 
round  which  its  tendon  turns  to  run  inwards.  The  soft  palate 
derives  its  blood-supply  from  the  posterior  palatine  of  the 
internal  maxillary  and  the  ascending  palatine  of  the  facial, 
which  latter  accompanies  the  levator  palati  to  the  soft  palate, 
and  is  cut  in  operations  dividing  that  muscle.  The  palate 
itself  is  enervated  by  palatine  branches  from  Meckel's  ganglion, 
while  the  tensor  palati  is  supplied  by  the  third  division  of 
the  fifth  through  the  otic  ganglion,  and  the  levator  palati, 
palato-pharyngei,  and  palato-glossi  and  azygos  uvulae  by  the 
eleventh  through  the  pharyngeal  plexus. 

Cleft  palate  consists  of  a  median  cleft,  which  may  vary  from 
a  bifid  uvula  to  a  complete  separation,  involving  both  soft 
and  hard  palates,  and  extending  up  to  the  premaxilla.  Com- 
plete cases  may  be  either  uni-  or  bilateral,  the  nasal  septum 
frequently  fusing  with  one  side  in  the  former.  When  the  cleft 
is  quite  complete,  it  generally  passes  on  either  side  of  the 
premaxilla,  which  then  projects  forwards,  the  condition  being 
usually  associated  with  double  hare-lip.  It  is  well  to  note, 
however,  that  the  anterior  extremity  of  the  cleft  generally 
does  not  run  between  the  lateral  incisor  and  canine,  but  between 
the  central  and  lateral  incisors,  owing  to  a  want  of  union 
between  the  two  centres  of  which  each  lateral  mass  of  the 
premaxilla  is  composed  (the  central  or  central  incisor  portion 
being  called  the  endo-gnathion,  and  the  lateral  the  meso- 
gnathion,  while  the  rest  of  the  maxilla  is  called  the  exo- 
gnathion).  Sometimes  this  splitting  involves  the  tooth  germ 
of  the  lateral  incisor,  a  supernumerary  incisor  being  produced. 

The  height  of  the  arch  of  the  palate  is  of  importance  in  some 
cases  where  an  osteoplastic  flap  is  used  to  remedy  the  condi- 
tion, those  cases  presenting  a  high  arch  being  the  more  hope- 


io8  SURGICAL  ANATOMY 

ful.  Sometimes  a  muco-periosteal  flap  is  taken.  The  opera- 
tion, where  the  hard  palate  is  involved,  is  called  uranoplasty, 
and  in  either  case  the  incision  is  made  close  to  the  alveolar 
border  and  not  extended  as  far  back  as  the  position  of  the 
wisdom  tooth,  so  as  to  preserve  the  blood-supply. 

Staphylorrhaphy  is  the  refreshing  and  bringing  together  of 
the  edges  of  a  cleft  of  the  soft  palate.  In  such  cases  it  is 
frequently  necessary  to  divide  the  tensor  and  levator  palati 
muscles  in  order  to  relax  the  parts,  and  this  may  be  done  by 
a  lateral  cut  with  scissors  parallel  to  the  cleft  (Bryant),  or 
by  introducing  a  narrow-bladed  knife,  with  the  edge  upwards, 
in  front  and  to  the  inside  of  the  hamular  process  till  the 
point  presents  at  the  upper  part  of  the  cleft,  which  cuts 
the  tensor,  and  then  on  withdrawing  it  cuts  the  levator 
posteriorly  (Pollock).  In  Ferguson's  method  a  knife  with 
the  blade  at  right  angles  to  the  handle  is  passed  up  through 
the  cleft,  and  the  levator  cut  on  the  posterior  surface  of  the 
palate,  the  tensor  being  left  intact. 

Tonsil. — The  tonsil  is  composed  of  lymphoid  tissue,  and  is 
situated  between  the  pillars  of  the  fauces,  being  kept  in  posi- 
tion by  fibrous  bands,  which  connect  its  deep  surface  with 
the  muscles  of  the  palatine  arches.  This  deep  surface  is 
closely  in  relation  to  the  superior  constrictor  of  the  pharynx, 
but  is  not  as  near  the  external  carotid  artery,  which  lies  in 
loose,  fatty  tissue  about  an  inch  behind,  and  considerably 
external  to  the  tonsil.  Thus  there  is  practically  no  possi- 
bility of  wounding  the  carotid  in  the  operation  of  tonsillotomy , 
save  where,  in  old  age,  the  vessel  has  become  very  tortuous. 
The  facial  or  ascending  pharyngeal  arteries  or  glosso-pharyn- 
geal  nerve  are  in  greater  danger  of  being  wounded.  The  inner 
or  free  surface  is  convex,  and  presents  numerous  depressions 
corresponding  to  the  orifices  of  the  crypts.  A  small  depression 
at  the  upper  extremity  is  known  as  the  supratonsillar  fossa, 
and  is  said  to  represent  the  pharyngeal  extremity  of  the  second 
branchial  cleft.  The  blood-supply  is  abundant,  being  derived 
from  branches  of  the  facial,  ascending  pharyngeal  of  the 
external  carotid,  descending  palatine  branches  of  the  internal 
maxillary  and  small  branches  of  the  dorsalis  linguae.  The 
veins  form  a  plexus  on  the  deep  surface,  and  communicate 
with  the  pharyngeal  veins.  The  lymphatics  communicate 
with  the  deep  cervical  glands  which  overlie  the  large  vessels 


THE  TONSIL  AND  PHARYNX  109 

behind  the  angle  of  the  lower  jaw.  The  tonsil  varies  con- 
siderably in  sizte  within  normal  limits,  and  in  tonsillitis  or 
cvunnche  tonsillaris  may  become  very  much  enlarged,  the 
two  tonsils  meeting  in  the  middle  line,  and  leaving  a  very 
small  breathing  space,  while  swallowing  becomes  very  diffi- 
cult. Where  the  enlargement  becomes  chronic,  tonsillotomy 
has  frequentty  to  be  performed.  Deafness  is  frequently  com- 
plained of  in  cases  of  enlarged  tonsils,  being  due,  probably,  to 
accompanying  hypertrophy  of  the  lining  membrane  of  the 
Eustachian  tube  rather  than  to  direct  pressure.  Decompo- 
sition of  secretions  retained  in  the  crypts  frequently  occurs, 
giving  rise  to  fcetid  breath,  and  calculi  may  form,  and  give 
rise,  through  irritation  of  the  glosso-pharyngeal  nerve,  to 
a  spasmodic  cough.  Tonsillar  abscesses,  which  not  infrequently 
complicate  scarlet  fever,  occur  interstitially  or  between  the 
tonsil  and  the  pharyngeal  wall.  Movements  of  the  jaw  are 
interfered  with,  and  the  glands  at  the  angle  of  the  jaw 
enlarge.  Such  abscesses  may  perforate  the  pharyngeal  wall, 
and  assume  a  large  size,  the  greatest  danger  being  septic  peri- 
arteritis  of  the  internal  carotid,  with  consequent  bursting  and 
fatal  haemorrhage.  In  opening  such  abscesses  the  edge  of  the 
bistoury  should  be  turned  toward  the  uvula,  the  incision 
being  made  from  without  inwards  toward  the  middle  line. 
Lympho- sarcoma  sometimes  occurs  in  the  tonsil  de  novo. 
Carcinoma  is  generally  secondary,  and  rapid  involvement  of 
the  glands  of  the  neck  generally  follows.  Such  cases  may  be 
treated  through  an  oblique  incision  in  front  of  the  sterno- 
mastoid,  which  enables  one  to  deal  with  primary  disease  and 
affected  glands. 

The  PHARYNX  extends  from  the  basis  cranii  to  the  lower 
border  of  the  sixth  cervical  vertebra.  It  is  about  5  inches 
long,  and  is  very  distensible.  It  is  common  to  both  respiratory 
and  digestive  tracts,  and  may  be  divided  into  naso-pharyngeal, 
b^ccal,  and  laryngeal  portions. 

The  NASO-PHARYNGEAL  portion  is  situated  above  the  soft 
palate  and  behind  the  nasal  fossae.  Its  postero-superior  wall 
is  formed  by  the  basis  cranii,  anterior  arch  of  the  atlas,  and 
body  of  the  axis,  together  with  their  muscles  and  ligaments. 
The  Eustachian  tubes  project  on  the  lateral  walls,  while  from 
their  lower  borders  folds  of  mucous  membrane,  known  as  the 
salpingo-pkaryngeal  folds,  extend  downwards.  Behind  the 


i io  SURGICAL  ANATOMY 

Eustachian  tubes,  and  beneath  the  petrous  bones,  are  lateral 
recesses  known  -as  the  fossa  of  Rosenmnller*,  and  here  the 
pharynx  is  widest. 

The  BUCCAL  PORTION  extends  from  the  arch  of  the  soft 
palate  to  the  epiglottis  and  upper  extremity  of  the  larynx. 
In  front  it  communicates  with  the  mouth  through  the  isthmus 
of  the  fauces,  below  which  it  is  bounded  by  the  dorsum  of  the 
tongue,  while  laterally  it  is  bounded  by  the  pillars  of  the 
fauces  and  tonsil. 

The  LARYNGEAL  PORTION  extends  the  whole  length  of  the 
larynx  from  its  upper  extremity  to  the  lower  border  of  the 
cricoid.  It  is  the  longest  but  least  capacious  portion.  On 
each  side,  in  front,  below  the  great  cornu  of  the  hyoid  and 
between  the  larynx  and  pharyngeal  wall  is  the  pyriform  fossa. 
The  pharynx  is  narrowest  at  its  junction  with  the  oesophagus, 
just  at  the  cricoid  cartilage,  and  here,  therefore,  foreign 
bodies  are  most  apt  to  lodge.  This  point  is  about  6  inches 
from  the  teeth,  and  cannot  be  reached  by  the  finger.  The 
walls  of  this  portion  of  the  pharynx  are  in  contact,  save  in 
swallowing,  forming  a  crescentic  slit,  with  the  concavity 
directed  forwards. 

The  pharyngeal  wall  consists  of  mucous  membrane,  pharyn- 
geal aponeurosis,  and  muscles.  Outside  of  these  is  the  thin 
bucco-pharyngeal  fascia,  which  invests  the  buccinator  in  front. 
The  mucous  membrane  is  vascular,  prone  to  inflammatory 
affections,  which  may  spread  to  the  Eustachian  tube,  and  so 
to  the  ears,  and  contains  much  lymphoid  tissue,  which — in  the 
child,  at  least — forms  a  distinct  mass  in  the  posterior  wall  of 
the  pharynx,  stretching  between  the  Eustachian  tubes,  known 
as  the  pharyngeal  tonsil  of  Luschka.  It  frequently  becomes 
hypertrophied,  giving  rise  to  post-nasal  adenoids,  which  may 
block  the  posterior  nares  or  Eustachian  tubes,  causing  deafness. 

The  pharyngeal  aponeurosis  is  a  thin  fibrous  sheet,  which  is 
best  developed  posteriorly  where  the  muscles  are  weakest. 
The  muscles  consist  of  the  stylo-  and  palato-pharyngei,  together 
with  the  three  constrictors,  which  latter  overlap  one  another 
from  below  upwards.  The  bucco-pharyngeal  fascia  has  very 
lax  connections  with  the  surrounding  parts,  and  so  permits  of 
considerable  movement,  while  it  also  favours  the  spread  of 
inflammatory  affections,  which  may  extend  to  the  posterior 
mediastinum,  or  even  to  the  diaphragm. 


THE  PHARYNX  in 

A  rejfo-pharyngeal  lymphatic  gland  is  situated  in  the  loose 
tissue  opposite  the  axis,  which  receives  lymph  from  the  nares, 
and  is  prone  to  suppuration.  An  acute  post-  or  retro-pharyn- 
geal abscess  may  originate  in  the  cellular  tissue  or  from  this 
gland,  in  front  of  the  prevertebral  layer  of  deep  cervical 
fascia,  and  present  on  the  posterior  pharyngeal  wall,  causing 
difficulty  in  respiration  and  in  swallowing.  Chronic  abscess 
in  this  situation  generally  arises  from  cervical  caries,  and  is, 
therefore,  behind  the  prevertebral  layer  of  the  deep  cervical 
fascia.  Retro-pharyngeal  abscesses  generally  burst  into  the 
mouth,  but  may  pass  behind  the  great  vessels,  and  present  to 
one  side  or  other  of  the  sterno-mastoid.  The  acute  abscess  is 
best  treated  by  a  vertical  mesial  incision  through  the  mouth, 
keeping  the  head  low  to  prevent  the  pus  reaching  the  larynx. 
In  order  to  prevent  sepsis,  the  tubercular  abscess  is  best 
evacuated  through  an  incision  along  the  posterior  border  of 
the  sterno-mastoid,  beginning  at  the  tip  of  the  mastoid  process. 
The  deep  structures  are  divided  by  a  blunt  dissector,  care 
being  taken  to  avoid  the  great  vessels,  until  the  abscess  is 
reached.  Lateral  pharyngeal  abscess  may  be  similarly 
treated,  care  being  necessary  to  diagnose  between  abscess 
and  aneurism  of  the  internal  carotid. 

Posteriorly  the  pharynx  is  in  relation  to  the  six  upper  cer- 
vical vertebrae,  anterior  common  ligament,  prevertebral 
muscles  and  fascia,  and  retro-pharyngeal  glands.  Laterally 
it  is  related  to  the  internal  carotid  artery,  internal  jugular 
vein,  and  ninth,  tenth,  eleventh,  and  twelfth  cranial  nerves 
and  sympathetic.  These  structures  may  be  wounded  by 
instruments,  introduced  through  the  mouth,  penetrating  the 
pharynx.  The  pharynx  is  also  in  relation  to  the  styloid 
process  and  muscles  which  arise  from  it,  the  posterior  belly 
of  the  digastric  and  internal  pterygoid  muscles,  and  the 
parotid  gland.  Toward  its  lower  extremity  it  is  more  super- 
ficial, and  is  related  to  the  common  carotid  and  its  branches, 
the  first  portions  of  the  lingual  and  facial  arteries,  the  laryn- 
geal  nerves,  and  lateral  lobe  of  the  thyroid.  Pharyngotomy 
may  be  performed  for  the  removal  of  tumours,  either  laterally, 
through  an  incision  similar  to  that  for  ligature  of  the  lingual 
artery,  or  mesially.  The  tumours  likely  to  occur  are  naso- 
pharyngeal  fibroma  and  sarcoma,  the  latter  frequently  invading 
the  nasal  cavities  and  orbit. 


[12  SURGICAL  ANATOMY 


THE   NECK 

Surface  Anatomy. 

The  neck  is  bounded  above  by  a  line  drawn  along  the 
lower  border  of  the  lower  jaw  to  the  angle,  thence  to  the 
mastoid  process,  and  so  to  the  superior  curved  line  and 
external  occipital  protuberance  ;  below,  by  a  line  from  the 
suprasternal  notch  along  the  upper  border  of  the  clavicle  to 
the  acromion,  and  from  thence  to  the  spine  of  the  vertebra 
prominens  (seventh  cervical).  It  is  pretty  constant  in 
length — generally  about  5  inches. 

The  hyoid  bone,  which  is  on  the  level  of  the  fourth  cervical 
vertebra,  divides  the  anterior  portion  of  the  neck  into  two 
triangles,  of  each  of  which  it  forms  the  base — an  upper,  or 
SUBMAXILLARY,  which  is  best  seen  when  the  head  is  thrown 
back,  whose  sides  are  formed  by  the  rami  of  the  jaw,  and  a 
lower,  or  INFRA-HYOID,  whose  sides  are  formed  by  the  sterno- 
mastoid  muscles.  The  latter,  again,  is  divided  into  two 
carotid  triangles  by  the  middle  line  of  the  neck,  which  presents 
several  points  of  importance.  Between  the  hyoid  bone  and 
thyroid  cartilage  the  thyro-hyoid  membrane  extends.  The 
vocal  cords  are  situated  about  the  level  of  the  middle  of  the 
thyroid  crest.  The  lateral  lobes  of  the  thyroid  gland  lie  to 
either  side  of  the  thyroid  cartilage.  Below  the  thyroid 
cartilage  comes  the  crico-thyroid  membrane  which  connects 
these  structures,  and  through  which  laryngotomy  may  be 
done,  by  means  of  a  small  transverse  incision  as  close  to  the 
cricoid  as  possible,  so  as  to  avoid  damage  to  the  crico-thyroid 
vessels.  The  cricoid  cartilage  forms  a  prominent  and  useful 
landmark,  even  in  infants.  It  is  on  a  level  with  the  fifth 
or  sixth  cervical  vertebra,  and  the  commencement  of  the 
oesophagus  lies  behind  it.  Foreign  bodies  too  large  to  be 
swallowed  frequently  lodge  at  this  level.  The  carotid  artery 
is  conveniently  ligatured  just  above  the  point  where  it  is 
crossed  by  the  omo-hyoid  muscle  on  a  level  with  the  cricoid 
cartilage,  the  tubercle  of  the  sixth  cervical  vertebra  forming 
a  further  guide.  The  lower  margin  of  the  cricoid  corresponds 

112 


THE  NECK  113 

with  the  junction  of  larynx  and  trachea.  The  trachea  is  not 
easily  made  out  superficially,  as  it  passes  in  deeply,  lying 
about  ij  inches  from  the  surface  at  the  suprasternal  notch, 
above  which  point  lie  the  first  seven  rings  of  the  trachea. 
The  inferior  thyroid  vein  lies  in  front  of  the  trachea,  below  the 
isthmus  of  the  thyroid.  The  suprasternal  notch  is  generally 
opposite  the  lower  border  of  the  second  dorsal  vertebra,  but 
may  be  opposite  the  third.  The  anterior  jugular  veins,  which 
commence  in  the  submaxillary  region,  descend  on  the  sterno- 
hyoid  muscles  to  either  side  of  the  middle  line,  and  then 
pierce  the  fascia  just  above  the  clavicle.  Behind  the  sterno- 
clavicular  joint  lie  the  commencement  of  the  innominate  vein, 
the  innominate  artery  on  the  right  and  the  carotid  on  the  left, 
and,  more  deeply,  the  lung  and  pleura. 

The  STERNO-MASTOID  REGION  is  that  which  is  covered  by 
the  muscle  of  that  name.  The  muscle  presents  a  small  fossa — 
the  fossa  supraclavicularis  minor — between  its  two  heads  and 
just  above  the  sterno-clavicular  articulation,  the  base  of 
which  corresponds  on  the  right  side  with  the  bifurcation  of 
the  innominate,  and  on  the  left  is  in  front  of  the  common 
carotid,  while  the  internal  jugular  vein  lies  a  little  external. 
Thus  these  important  structures  are  in  danger  in  subcutaneous 
tenotomy  of  the  sternal  head.  The  external  jugular  vein 
crosses  the  muscle  superficially  from  above,  downwards  and 
backwards,  in  a  line  drawn  from  the  angle  of  the  jaw  to  the 
middle  of  the  clavicle,  while  the  anterior  jugular  vein  generally 
runs  along  the  anterior  border  of  the  muscle.  On  its  deep 
surface  the  spinal  accessory  nerve  passes  obliquely  down  and 
backwards,  and  enters  the  muscle,  which  it  supplies,  about 
1 1  inches  below  the  mastoid  process,  at  the  junction  of  its 
anterior  and  middle  thirds.  On  leaving  the  muscle,  it  enters 
the  posterior  triangle  of  the  neck  midway  between  the  occiput 
and  clavicle,  to  end  in  the  deep  surface  of  the  trapezius. 

The  posterior  border  of  the  sterno-mastoid  nearly  corre- 
sponds with  that  of  the  scalenus  anticus,  the  guide  to  the 
subclavian  artery. 

The  apex  of  the  lung  rises  well  into  the  neck,  extending 
generally  ij  inches  above  the  clavicle,  under  cover  of  the 
clavicular  portion  of  the  sterno-mastoid,  sterno- thyroid,  and 
part  of  the  scalenus  anticus,  and  first  part  of  the  subclavian 
vessels. 

8 


114  SURGICAL  ANATOMY 

The  POSTERIOR  TRIANGLE  of  the  neck  is  the  space  bounded 
by  the  sterno-mastoid  in  front,  the  trapezius  behind,  and  the 
middle  third  of  the  clavicle  below.  The  surface  of  the 
triangle  is  depressed  above  the  clavicle  forming  the  supra- 
clavicular  fossa,  which  is  traversed  by  the  subclavian  vessels 
and  cords  of  the  brachial  plexus.  The  subclavian  artery, 
lying  on  the  first  rib,  may  be  felt  in  this  depression,  close  to 
the  border  of  the  sterno-mastoid,  and  may  be  compressed 
against  the  rib  by  pressure  applied  downwards  and  inwards. 
The  posterior  belly  of  the  omo-hyoid  can  be  felt,  and  sometimes 
seen,  as  a  thin  cord  just  above,  and  running  parallel  to,  the 
clavicle.  In  the  upper  part  of  the  fossa  the  transverse  process 
of  the  seventh  cervical  vertebra  may  be  felt  on  deep  pressure. 

The  POSTERIOR  REGION  of  the  neck  is  bounded  on  either  side 
by  the  anterior  edge  of  the  trapezius,  and  presents  two  lateral 
masses,  formed  by  the  trapezius  and  complexus  muscles  on 
either  side,  separated  by  a  slight  central  depression,  under 
which  lies  the  ligamentum  nuchce,  extending  from  the  occipital 
protuberance  to  the  spine  of  the  vertebra  prominens  (seventh 
cervical).  The  spine  of  the  axis  may  be  felt  on  deep  pressure 
at  the  upper  end  of  the  central  depression. 

The  skin  of  the  neck  is  smooth,  and  freely  movable  in 
front,  and  particularly  so  in  the  submaxillary  region,  where 
advantage  is  taken  of  this  in  performing  certain  plastic 
operations  about  the  mouth,  while  the  same  property  favours 
cicatricial  contraction  and  deformity.  The  platysma  myoides 
is  quite  subcutaneous,  and  by  its  connections  causes  turning 
in  of  the  edges  of  wounds  made  across  the  line  of  its  fibres, 
which  run  upwards  and  forwards.  Sometimes  the  accumula- 
tion of  subcutaneous  fat  in  this  region  may  be  great,  and  give 
rise  to  a  pendulous  fold  known  as  a  '  double  chin.'  At  the 
back  of  the  neck  the  skin  is  thicker  and  more  adherent, 
contains  numerous  sebaceous  glands,  is  generally  exposed  to 
friction,  and  is  a  favourite  seat  of  boils  and  carbuncles.  As 
the  subcutaneous  tissues  are  dense,  and  the  blood-supply  not 
very  abundant,  these  affections  are  frequently  painful,  and 
sloughing  is  not  uncommon. 

The  cervical  facia  consists  of  three  principal  layers  : 
(i)  A  superficial  investing  layer,  which,  attached  to  the  liga- 
mentum nuchae  behind,  runs  round  the  neck,  splitting  as  it 


THE  NECK 


does  S.G  to  enclose  the  trapezius  and  sterno-mastoid  muscles, 
to  join  its  neighbour  of  the  opposite  side  in  front,  where  it 


23          4 


FIG.   ii. — DEEP  DISSECTION  OF  THE  LEFT  SIDE  OF  THE  NECK 
(Buchanan,  after  Spalteholz.) 


1.  Transverse  facial  artery.  16. 

2.  Stensen's  duct.  17. 

3.  Socia  parotidis.  18. 

4.  Parotid  gland.  19. 

5.  Superficial  temporal  artery.  20. 

6.  Internal  maxillary  artery.  21. 

7.  Posterior  auricular  artery.  22. 

8.  Occipital  artery.  23. 

9.  Occipital  artery.  24. 
10.  Great  occipital  nerve.  25. 
n.  Internal  carotid  artery.  26. 

12.  Deep  cervical  glands.  27. 

13.  Phrenic  nerve.  28. 

14.  Scalenus  anticus  muscle.  29. 

15.  Transverse  cervical  artery.  30. 


Suprascapular  artery. 
Thyroid  axis. 

Subclavian  artery  (first  part 
Inferior  thyroid  artery. 
Ascending  cervical  artery. 
Anterior  belly  of  omo-hyoid. 
Common  carotid  artery. 
Internal  jugular  vein. 
Pneumogastric  nerve. 
Superior  thyroid  artery. 
Superior  laryngeal  artery. 
External  carotid  artery. 
Lingual  artery. 
Facial  artery. 
Mental  artery. 


has  an  attachment  to  the  hyoid  bone.     Above,  following  it 
from  behind,  it  is  attached  to  the  superior  curved  line  of  the 

8—2 


n6  SURGICAL  ANATOMY 

occiput,  mastoid  process,  and  cartilage  of  the  external 
auditory  meatus  ;  then  it  splits  to  enclose  the  parotid  gland, 
(parotid  capsule — the  anterior  layer  being  attached  to  the 
zygoma  and  the  posterior  to  the  styloid  process  and  angle 
of  the  jaw,  forming  the  stylo-maxillary  ligament),  and  finally 
is  attached  to  the  margin  of  the  lower  jaw.  Below  it  is 
attached  to  the  clavicle  and  manubrium  sterni,  the  fascia 
splitting  close  to  its  insertion  into  the  latter  to  enclose  the 
sternal  head  of  the  sterno-mastoid,  some  lymphoid  tissue,  and 
the  anterior  jugular  vein.  The  anterior  layer  is  attached  to 
the  front  .of  the  manubrium  and  the  posterior  to  the  back  of 
the  bone,  and  it  is  this  compartment  which  is  opened  into 
in  dividing  the  sternal  head  of  the  sterno-mastoid.  This 
superficial  layer  supplies  a  capsule  to  the  subm axillary  gland. 

(2)  A  PRETRACHEAL  LAYER  lies  immediately  under  the  super- 
ficial layer  in  front,  and  invests  the  anterior  group  of  muscles 
(sterno-hyoid,    etc.).     It    also    furnishes    a    capsule    for    the 
thyroid  gland,  helping  to  connect  it  with  the  cricoid  cartilage, 
and  laterally  forms  the  anterior  portion  of  the  carotid  sheath. 
Above,  it  is  attached  to  the  hyoid  bone  ;  below,  it  passes 
behind  the  sternum  into  the  thorax,  where  it  fuses  with  the 
fibrous  pericardium.     This  layer  extends  into  the  posterior 
triangle  of  the  neck,  where  it  invests  the  posterior  belly  of  the 
omo-hyoid.     Above  this  it  fuses  with  the  deep  aspect  of  the 
sterno-mastoid  sheath  (layer  No.  i),  while  below  it  is  attached 
to  the  clavicle  and  sheath  of  the  subclavius  muscle  (whence  it 
becomes   continuous   with    the    costo-coracoid    membrane). 

(3)  A  PREVERTEBRAL  LAYER  runs  across  the  neck  in  front  of 
the  prevertebral  muscles,  forming  a  partition  between  the 
posterior  muscular  and  anterior  visceral  segment  of  the  neck. 
Above,  it  is  attached  to  the  basis  cranii,  and  below  it  is  con- 
tinued into  the  thorax.     Laterally,   this  layer  fuses  in  the 
upper  part  of  the  neck  with  the  carotid  sheath,  the  posterior 
part  of  which  it  forms ;  while  in  the  lower  portion  of  the  neck 
it  extends  laterally  into  the  posterior  triangle  lying  over  the 
subclavian   vessels   and   cords   of   the   brachial   plexus,   and 
accompanying  them  into  the  axilla.     As  the  deep  cervical 
fascia  is  very  tense  and  strong,  abscesses  in  the  neck  have 
generally  difficulty  in  reaching  the  surface,  except  those  which 
occur  in  the  front  of  the  neck  just  under  the  superficial  in- 
vesting layer,  which  is  thin  at  this  part.     In  many  instances. 


THE  NECK  117 

therefore,  abscesses,  especially  those  occurring  between 
layers  Nos.  2  and  3,  instead  of  coming  to  the  surface,  penetrate 
some  of  the  structures  in  the  neck,  such  as  the  trachea  and 
oesophagus,  and  sometimes  the  pleura,  or  even  the  great 
vessels.  A  prevertebral  abscess,  lying  as  it  does  behind  layer 
No.  3,  might  be  guided  by  it  down  into  the  posterior  medias- 
tinum, or,  following  the  layer  covering  the  subclavian  vessels, 
reach  the  posterior  triangle  or  the  axilla.  Not  infrequently, 
however,  these  abscesses  point  in  the  pharynx  or  oesophagus. 
Layers  Nos.  2  and  3  form  a  compartment  for  the  pharynx, 
larynx,  and  great  vessels,  etc.,  and  as  these  lie  loosely  in  this 
space,  surrounded  by  connective  tissue,  they  are  free  to  move 
with  respiration  and  deglutition,  and  to  accommodate  them- 
selves to  pressure  of  tumours,  etc. 

The  muscles  of  the  neck  may  be  considered  in  three 
groups  :  (i)  Trapezius  and  sterno-mastoid,  constituting  the 
superficial  group  ;  (2)  sterno-  and  omo-hyoid,  the  anterior 
group  ;  (3)  prevertebral,  scalene  or  lateral  vertebral,  and  post- 
vertebral,  the  deep  vertebral  group. 

Of  these  the  STERNO-MASTOID  is  the  most  important.  The  two 
heads,  one  arising  from  the  front  of  the  manubrium  as  a  rounded 
tendon,  and  the  other  from  the  inner  third  of  the  clavicle  as 
a  mixed  muscular  and  tendinous  bundle,  are  at  first  separate, 
but  the  sternal  portion,  as  a  rule,  rapidly  widens  out,  and 
conceals  the  other.  The  clavicular  head  is  in  relation  below 
to  the  subclavian  vein  and  to  the  external  jugular  vein  on 
its  way  to  join  it  ;  the  interspace,  to  the  bifurcation  of  the 
innominate  on  the  right,  which,  however,  lies  deeply.  The 
great  vessels  of  the.neck  and  vagus  nerve  lodged  in  the  carotid 
sheath,  and  the  sympathetic  lying  behind  it,  are  overlapped 
by  the  anterior  border  of  the  muscle  over  a  considerable 
portion  of  their  extent,  while  the  spinal  accessory  nerve  runs 
obliquely  downwards  and  backwards  behind  it,  about  a 
couple  of  inches  below  the  mastoid  process.  The  deep  lym- 
phatic glands  of  the  neck  are  covered,  and  the  lateral  lobe 
of  the  thyroid  is  overlapped  by  it.  On  the  anterior  border  of 
the  muscle  at  the  level  of  the  great  cornu  of  the  hyoid  the 
internal  jugular  vein  is  joined  by  its  lingual,  facial,  and 
superior  thyroid  branches.  From  the  centre  of  the  posterior 
border  of  the  muscle  several  nerves,  derived  from  the  cervical 
plexus,  radiate :  (i)  The  small  occipital  runs  upwards  along 


ii8  SURGICAL  ANATOMY 

the  posterior  border  of  the  muscle.  (2)  The  great  auricular 
runs  vertically  upwards  across  the  muscle  to  the  ear.  (3)  The 
superficial  cervical  runs  transversely  across  the  muscle  ;  arid 
(4)  the  descending  suprasternal,  clavicular,  and  acromial 


•20 


1C, 


FIG.  12.— DIAGRAM  OF  A  TRANSVERSE  SECTION  OF  THE  NECK  AT  THE 
LEVEL  OF  THE  SEVENTH  CERVICAL  VERTEBRA,  SHOWING  THE 
ARRANGEMENT  OF  THE  DEEP  CERVICAL  FASCIA,  AND  THE  POSITIONS 
OF  OTHER  STRUCTURES. 

(From  Buchanan's  "Anatomy.") 


1.  Burns's  space. 

2.  Trachea. 

3.  Muscular  compartment. 

4.  Lateral  lobe  of  thyroid  body. 

5.  CEsophagus. 

6.  Descendens  cervicis  nerve. 

7.  Common  carotid  artery. 

8.  Internal  jugular  vein. 

9.  Pneumogastric  nerve. 

10.  Platysma  myoides. 

11.  Sympathetic  nerve. 

12.  Longus  colli. 

13.  Sterno-cleido-mastoid. 

14.  External  jugular  vein. 

15.  Vertebral  vessels. 


16.  Trapezius. 

17.  Semispinalis. 

18.  Splenius. 

19.  Complexus. 

20.  Levator  anguli  scapulae. 

21.  Scalenus  medius. 

22.  Scalenus  anticus. 

23.  Carotid  lamina  of  fascia. 

24.  Prevertebral  lamina  of  fascia. 

25.  Pretracheal  lamina  of  fascia. 

26.  Anterior  belly  of  omo-hyoid. 

27.  Superficial  lamina  of  fascia. 

28.  Sterno-hyoid. 

29.  Sterno-thyroid. 


branches  radiate  downwards  to  the  parts  indicated.  In 
torticollis,  or  wry-neck,  which  is  generally  due  to  spasm  of  the 
muscles,  the  head  is  leant  to  the  affected  side,  and  slightly 
bent  forwards,  while  the  face  looks  toward  the  sound  side. 


THE  NECK  119 

The  mascle,  and  particularly  its  sternal  head,  becomes  very 
prominent,  and  a  lateral  curvature  of  the  spine  frequently 
exists.  In  some  of  the  more  severe  cases  the  trapezius  and 
scalene  muscles  may  also  be  affected.  The  condition  may  be 
due  to  some  affection  of  the  muscle  itself  (permanent  torti- 
collis), or  may  be  due  to  irritation  of  the  spinal  accessory  nerve 
(spasmodic  torticollis).  The  spasmodic  form  is  sometimes 
induced  by  reflex  irritation,  such  as  lymphadenitis  in  the 
posterior  triangle  affecting  one  of  the  cervical  nerves,  of  which 
the  second  supplies  the  muscle,  in  addition  to  the  spinal 
accessory.  In  the  permanent  types  of  torticollis  the  sternal 
head  of  the  muscle  may  be  divided  either  subcutaneously  by 
a  puncture  f  inch  above  the  clavicle  in  front  of  the  muscle, 
the  tenotome  being  made  to  cut  out,  or  by  an  open  incision 
also  |  inch  above  the  clavicle.  In  the  spasmodic  type  the 
spinal  accessory  nerve  may  be  divided  or  resected,  an  incision 
being  made  along  the  anterior  border  of  the  muscle,  and  the 
posterior  belly  of  the  digastric  and  transverse  process  of  the 
atlas  being  taken  as  guides.  Sometimes  it  is  also  well  to  cut 
the  communicating  branches  of  the  third  and  fourth  cervical 
nerves.  The  muscle  may  also  be  affected  by  a  congenital 
tumour,  sometimes  associated  with  shortening,  and  conse- 
quent torticollis,  which  may  be  due  to  syphilis  or  to  injury 
during  delivery. 

Of  the  prevertebral  muscles  the  SCALENE  MUSCLES  arise 
from  the  transverse  processes  of  several  of  the  cervical 
vertebrae,  the  ANTICUS  from  the  anterior  tubercles,  and  the 
MEDIUS  and  POSTICUS  from  the  posterior.  The  two  former  are 
inserted  into  the  first  rib,  the  subclavian  artery,  cords  of  the 
brachial  plexus,  and  the  pleura  lying  between  them,  while 
the  subclavian  vein  passes  in  front  of  the  anticus.  The 
scalenus  posticus  is  inserted  into  the  second  rib.  They  are 
all  supplied  by  the  lower  cervical  nerves.  The  MUSCLES  OF 
THE  BACK  OF  THE  NECK  are  in  direct  continuity  with  those  of 
the  back  generally,  and  form  two  large  lateral  masses,  with 
a  median  vertical  depression  opposite  the  spines  of  the 
vertebrae.  These  muscles,  as  seen  in  transverse  section  of 
the  neck,  may  be  considered  as  forming  five  layers,  the  most 
superficial  being  formed  by  the  trapezius,  the  second  by  the 
splenius  capitis  and  colli  (the  levator  anguli  scapulae  inter- 
digitating  between  the  trapezius  and  the  splenius  colli  in 


120  SURGICAL  ANATOMY 

front),  the  third  by  the  complexus,  fourth  by  the  semispinalis 
colli,  and  the  fifth  by  the  multifidus  spinae.  More  anteriorly, 
behind  the  splenius  colli  and  anterior  end  of  the  complexus, 
lie  from  without  inwards  the  trans versalis  cervicis  and  the 
trachelo  mastoid.  Between  the  complexus  and  semispinalis 
colli  lie  the  profunda  cervicis  artery  and  vein  (from  superior 
intercostal  or  subclavian).  The  infra-hyoid  muscles  comprise 
the  sterno-hyoid  and  thyroid,  omo-hyoid,  and  thyro-hyoid. 
Of  these  the  STERNO-THYROID,  arising  from  the  deep  surface 
of  the  sternum,  is  deeply  placed,  and  runs  parallel  to  the 
larynx  and  trachea.  The  THYRO-HYOID  practically  continues 
the  preceding  muscle  up  to  the  hyoid.  The  STERNO-HYOID 
arises  from  the  clavicle  and  also  from  the  deep  surface  of  the 
sternum,  but  superficial  to  the  sterno-thyroid,  and  passes  up 
to  the  hyoid  bone  internal  to  the  omo-hyoid.  The  OMO- 
HYOID  is  important  surgically,  as  its  anterior  portion  crosses 
the  common  carotid  artery  at  the  level  of  the  cricoid  cartilage, 
where  the  vessel  is  ligatured,  and  divides  the  anterior  triangle 
into  muscular  and  carotid  triangles,  while  the  posterior  belly 
divides  the  posterior  triangle  into  occipital  and  subclavian 
triangles,  the  latter  containing  the  portion  of  subclavian 
selected  for  ligature  of  that  artery.  It  is  inserted  above  into 
the  hyoid  between  the  thyro-hyoid  and  sterno-hyoid,  and 
below  into  the  superior  border  of  the  scapula,  while  the 
tendon  is  held  down  by  a  process  of  deep  cervical  fascia. 
The  omo-hyoids  are  said  by  their  action  to  render  the  pre- 
tracheal  layer  of  the  deep  cervical  fascia  tense,  and  so  protect 
the  deep  veins  from  the  pressure  of  the  sterno-mastoids  when 
contracting.  The  DIGASTRIC  is  also  of  importance,  as  with  the 
lower  border  of  the  jaw  it  forms  the  boundaries  of  the  triangle 
of  that  name.  Attached  posteriorly  to  the  digastric  groove 
beneath  the  mastoid  process  and  muscles  rising  from  it,  it 
runs  forwards  and  downwards  to  the  hyoid  bone  (to  which  its 
tendon  is  attached  by  a  process  of  cervical  fascia),  crossing 
the  carotid  artery  and  hypoglossal  nerve  in  its  course,  and 
then  turns  forwards  and  upwards  to  the  lower  border  of  the 
chin.  The  MYLO-HYOID  lies  under  the  digastric,  and  runs 
downwards  and  forwards  from  the  jaw  to  the  hyoid  bone  and 
to  a  median  raphe,  forming  a  diaphragm  for  the  floor  of  the 
mouth,  part  of  its  inner  surface  being  covered  with  mucous 
membrane,  and  separated  from  the  hyo-glossus  by  a  deep 


THE  NECK 


121 


portion  of  the  submaxillary  gland,  sublingual  gland,  and 
Wharton's  duct,  and  lingual  and  hypoglossal  nerves.  The 
HYO-GLOSSUS,  running  upwards  and  forwards  from  the  hyoid 
bone  to  the  side  of  the  tongue,  is  visible  behind  the  posterior 
margin  of  the  mylo-hyoid,  with  the  hypoglossal  nerve  and 
ranine  vein  running  horizontally  across  it,  the  former  being 
generally  the  upper.  The  lingual  artery  runs  on  the  deep 
surface  of  the  hyo-glossus. 

Submaxillary   Region. — The   submaxillary  region  may   be 
divided  into  a  median  submental  triangle,  common  to  both 


18  - 


14 


FIG.   13.— DEEP  DISSECTION  OF  THE  LEFT  SUBMAXILLARY  REGION. 
(From  Buchanan's  "  Anatomy.") 


1.  Sublingual  gland  (turned  up). 

2.  Dorsum  of  tongue. 

3.  Stylo-glossus  muscle. 

4.  Lingual  nerve. 

5.  Submaxillary  ganglion. 

6.  Submaxillary  gland  (deep  part). 

7.  Facial  artery. 

8.  Lingual  artery. 

9.  Superior  thyroid  artery. 


10.  External  carotid  artery. 

11.  Ranine  vein. 

12.  Hypoglossal  nerve. 

13.  Wharton's  duct. 

14.  Ranine  artery. 

15.  Sublingual  artery. 

16.  Genio-hyoid  muscle. 

17.  Genio-hyo-glossus  muscle. 

18.  Mandible  (in  section). 


sides,  a  digastric  triangle,  and  a  space  between  the  stylo- 
hyoid  and  digastric  which  widens  posteriorly.  The  sides  of 
the  SUBMENTAL  TRIANGLE  are  formed  by  the  anterior  bellies 
of  the  digastric,  the  base  by  the  hyoid  bone;  and  the  apex 
by  the  symphysis.  The  floor  is  formed  by  the  median 
raphe  and  portions  of  both  mylo-hyoids.  One  or  two  sub- 
mental  lymphatic  glands  are  generally  situated  at  the  apex 
of  the  triangle.  The  sides  of  the  DIGASTRIC  TRIANGLE  are 
formed  by  that  muscle  with  the  stylo-hyoid,  the  base  being 
the  lower  border  of  the  jaw  and  stylo-mandibular  ligament, 


122  SURGICAL  ANATOMY 

the  apex  being  the  intermediate  tendon  of  the  digastric.  On 
exposing  the  triangle,  the  submaxillary  gland  is  found  to  occupy 
most  of  the  space,  and  particularly  where  infected  by  car- 
cinoma may  overlap  the  margin  of  that  triangle.  On  turning 
the  gland  upwards,  we  find  that  the  floor  is  formed  in  front 
by  the  fibres  of  the  mylo-hyoid  running  downwards  and  for- 
wards, while  behind  it,  and  on  a  deeper  plane,  are  the  fibres  of 
the  hyo-glossus,  running  downwards  and  backwards,  and  crossed 
by  the  hypoglossal  nerve  and  ranine  vein  (the  former  generally 
above  the  latter),  running  parallel  forwards,  to  disappear 
beneath  the  posterior  border  of  the  mylo-hyoid.  Behind  the 
hyo-glossus,  and  still  deeper,  are  the  fibres  of  the  superior 
constrictor  of  the  pharynx,  also  running  downwards  and  back- 
wards. The  lingual  artery  is  given  off  just  opposite  the  tip  of 
the  great  cornu  of  the  hyoid,  and,  running  on  the  deep  surface 
of  the  hyo-glossus,  pursues  the  same  course  as  the  vein,  which 
is  superficial  to  the  muscle,  and  is  accordingly  taken  as  a 
guide.  The  artery  is  generally  ligatured  at  this  point  in  the 
so-called  lingual  triangle,  formed  by  the  ranine  vein  as  a  base, 
the  posterior  belly  of  the  digastric  posteriorly,  and  the  pos- 
terior border  of  the  mylo-hyoid  anteriorly,  the  fibres  of  the 
hyo-glossus  being  separated  in  order  to  get  at  the  artery. 
The  ligature  of  the  artery  on  each  side  generally  forms  a 
preliminary  to  excision  of  the  tongue. 

The  facial  artery  is  given  off  immediately  above  the  lingual, 
and  runs  up  to  the  angle  of  the  jaw,  and  then  runs  parallel  to 
and  just  under  the  ramus  of  the  jaw  to  the  anterior  border  of 
the  masseter.  It  lies  on  the  deep  surface  of  the  submaxillary 
gland,  which  separates  it  from  its  vein.  The  submental  branch 
of  the  facial  runs  along  the  under  border  of  the  jaw  to  the  sym- 
physis,  and  supplies  the  submaxillary  and  sublingual  glands. 
The  submaxillary  lymphatic  glands  lie  on  either  surface  of  the 
submaxillary  gland,  with  which  they  are  closely  connected, 
some  being  situated  within  the  capsule  of  the  gland  or  incor- 
porated in  the  gland  substance.  The  superficial  ones  drain 
the  nose,  cheek,  and  lips,  while  the  deeper  drain  the  salivary 
glands,  anterior  part  of  the  tongue,  and  floor  of  the  mouth. 
These  glands  are  frequently  the  seat  of  tubercular  and 
secondary  carcinomatous  infection.  They  and  their  ducts  are 
also  infected  by  inflammatory  affections,  a  very  acute  form 
being  known  as  Ludwig's  angina, 


THE  NECK  123 

Thetfiyoid  bone  possesses  very  considerable  mobility,  and 
hence  is  not  frequently  fractured,  save  by  severe  direct  violence, 
as  in  throttling.  As  a  rule,  the  great  cornu  is  the  part  broken 
off.  Where  fracture  occurs,  the  patient  has  much  difficulty 
in  speaking  and  other  movements  of  the  tongue,  and  especially 
in  swallowing,  owing  to  want  of  support  to  the  middle  con- 
strictor. The  bone  presents  many  attachments :  to  the 
tongue  (by  the  hyo-glossus  and  genio-hyo-glossus  and  hyo- 
glossal  ligament)  ;  to  the  epiglottis  (by  the  hyo-epiglottic 
ligament)  ;  to  the  lower  jaw;  base  of  the  skull,  sternum,  and 
scapula  ;  larynx  (by  the  thyro-hyoid  muscles  and  membrane) ; 
pharynx  (by  the  middle  constrictor). 

The  Infra-Hyoid  Region. — The  thyro-hyoid  membrane  ex- 
tends between  the  posterior  aspect  of  the  upper  border  of 
the  hyoid  bone  and  great  cornu,  and  the  upper  border  of  the 
thyroid  cartilage,  and  is  rather  over  an  inch  in  vertical  depth. 
This  arrangement  permits  of  the  ascent  of  the  larynx  behind 
the  hyoid  in  deglutition.  Between  the  under  surface  of  the 
hyoid  bone  and  the  anterior  aspect  of  the  membrane  the 
thyro-hyoid  bursa  is  placed.  This  sometimes  becomes  en- 
larged, necessitating  removal.  The  membrane  is  superficial 
in  front,  is  covered  laterally  by  the  sterno-,  thyro-,  and  omo- 
hyoid  muscles,  and  is  pierced  by  the  superior  laryngeal 
artery  and  internal  laryngeal  nerve.  The  deep  surface  is 
connected  by  a  pad  of  fatty  tissue  with  the  epiglottis  and 
aryteno-epiglottic  folds.  The  membrane  is  not  infrequently 
divided  in  suicidal  wounds,  as  are  likewise  the  epiglottis  and 
anterior  wall  of  the  pharynx.  The  superior  thyroid  artery 
and  internal  laryngeal  nerve  frequently  suffer,  while  the 
larger  vessels,  owing  to  their  mobility,  escape.  Division  of 
the  internal  laryngeal  nerve  causes  anaesthesia  of  the  laryn- 
geal mucous  membrane,  and  permits  particles  of  food  to 
enter  the  air  passages  and  set  up  septic  pneumonia.  An 
incision  made  through  the  membrane  affords  access  to  the 
upper  portion  of  pharynx  and  larynx,  and  is  sometimes  useful 
in  removing  foreign  bodies  or  tumours  from  these  parts. 

The  larynx  moves  up  and  down  in  certain  movements  of 
the  head  and  neck,  in  deglutition,  slightly  in  respiration,  and 
laterally  from  passive  movement.  It  is  more  highly  placed 
in  children  and  women  than  in  men,  the  cricoid  being  at  the 
level  of  the  lower  border  of  the  fourth  cervical  in  the  infant, 


124  SURGICAL  ANATOMY 

while  by  puberty  it  has  reached  the  adult  position,  opposite 
the  lower  border  of  the  sixth.  It  is  lined  with  mucous  mem- 
brane, which  is  continuous  with  that  of  the  pharynx  above 
and  trachea  below.  In  the  middle  line  it  is  quite  superficial, 
being  covered  only  by  skin,  subcutaneous  tissue,  and  deep 
fascia,  but  laterally  is  covered  by  the  sterno-,  thyro-,  omo- 
hyoid,  and  sterno-thyroid  muscles,  and  the  lateral  lobes  of 
the  thyroid  gland.  Posteriorly,  the  lumen  of  the  larynx  is 
maintained  at  the  expense  of  that  of  the  pharynx,  which  is 
generally  flattened.  Laterally,  on  each  side,  there  is  a  recess, 
the  pharyngo-laryngeal,  the  upper  extremity  of  which  (situated 
above  and  external  to  the  aryteno-epiglottic  folds,  and  in 
which  foreign  bodies  may  lodge)  is  known  as  the  pyriform 
fossa.  The  upper  aperture  of  the  larynx,  when  at  rest,  looks 
almost  directly  backwards.  It  is  bounded  in  front  by  the 
epiglottis,  laterally  by  the  aryteno-epiglottic  folds,  and  pos- 
teriorly by  the  arytenoid  cartilages  and  the  notch  between 
them.  The  interior  of  the  larynx  is  lined  by  mucous  membrane, 
which  varies  much  in  thickness  and  laxness,  according  to  the 
amount  of  subcutaneous  tissue.  The  thickest  portions  are 
at  the  aryteno-epiglottic  folds,  the  ventricle,  false  cords,  and 
laryngeal  portion  of  the  epiglottis,  and  these  are  particularly 
affected  in  laryngitis  and  oedema  of  the  glottis.  The  latter 
affection  is  a  very  serious  one,  which  specially  affects  the 
aryteno-epiglottic  folds  (not  the  vocal  cords),  and  so  may 
cause  asphyxia.  At  the  true  vocal  cords  the  mucous  mem- 
brane is  firmly  adherent,  and  presents  stratified  epithelium, 
whereas  at  other  parts  it  is  lined  with  ciliated  epithelium. 
Epithelioma  is  not  infrequently  found  at  the  point  of  junction 
of  the  two  forms  of  epithelium,  and  this  position  is  also  a 
favourite  one  for  papilloma.  The  mucous  membrane  is  rich 
in  mucous  glands,  except  at  the  vocal  cords,  and  these  glands 
are  specially  numerous  in  the  regions  of  the  arytenoids, 
ventricle,  and  base  of  the  epiglottis.  The  glands  become 
affected  in  chronic  glandular  laryngitis,  clergyman's  sore- 
throat,  etc.  The  mucous  membrane  receives  its  chief  nerve- 
supply  from  the  two  internal  laryngeal  nerves  (from  the 
superior  laryngeal  of  the  vagus),  and  is  extremely  sensitive 
to  contact  with  a  foreign  body,  calling  forth  spasm  and  reflex 
expulsive  cough,  by  which  entrance  of  such  bodies  to  the 
trachea  is  prevented.  When  these  nerves  are  divided,  this 


THE  NECK  125 

sensation  is  lost,  foreign  matter  may  enter  the  lungs,  and  so 
set  up  a  septic  broncho-pneumonia.  As  these  nerves  are 
also  inhibited  to  a  considerable  extent  by  chloroform,  it  is 
necessary  for  the  administrator  to  see  that  no  blood,  mucus, 
or  other  foreign  matter  is  inspired  during  narcosis.  The 
other  branch  of  the  superior  laryngeal  is  the  external  laryngeal, 
which  supplies  the  crico-thyroid,  while  the  recurrent  laryngeal, 
also  a  branch  of  the  vagus,  supplies  all  the  intrinsic  muscles, 
except  the  crico-thyroid.  The  mucous  membrane  receives  its 
blood  -  supply  from  three  vessels  on  either  side  —  superior 
laryngeal  and  crico-thyroid  from  the  superior  thyroid,  and 
inferior  laryngeal  from  the  inferior  thyroid — and  is  very 
vascular,  save  at  the  true  vocal  cords.  The  lymphatics  from 
parts  above  the  glottis  pass  upwards  and  outwards  through  the 
thyro-hyoid  membrane  to  end  in  glands  under  the  great  cornu 
of  the  hyoid,  or  at  the  bifurcation  of  the  common  carotid  ; 
while  those  from  below  the  glottis  terminate  in  glands  on  either 
side  of  the  trachea.  The  mucous  membrane  is  thrown  into 
two  antero-posterior  folds  on  either  side,  forming  the  vocal 
cords,  which  divide  the  larynx  into  three  compartments — an 
upper,  or  vestibule,  which  extends  from  the  aryteno-epiglottic 
folds  to  the  false  cords ;  a  middle,  between  the  false  and  true 
cords  ;  and  a  lower,  which  extends  from  the  true  cords  to  the 
lower  border  of  the  cricoid.  The  upper  pair  of  cords,  or 
false  cords,  are  not  so  markedly  developed,  do  not  closely 
approach  one  another,  and  do  not  produce  the  voice.  The 
true  vocal  cords,  or  inferior  thyro-arytenoid  ligaments,  are 
inserted  together  anteriorly  in  the  angle  of  junction  of  the 
thyroid  alae,  midway  between  the  median  notch  and  the  lower 
border,  while  posteriorly  they  diverge,  and  are  inserted  into 
the  processus  vocales  of  the  arytenoid  cartilages.  They 
consist  of  white  fibrous  tissue,  covered  with  stratified  mucous 
membrane.  The  lateral  wall  of  the  larynx,  in  the  middle 
compartment,  presents  a  recess,  or  pocket,  on  either  side — the 
ventricle,  from  which,  anteriorly,  is  given  off  a  small  diverti- 
culum,  the  laryngeal  saccule,  which  extends  upwards  be- 
tween the  false  vocal  cord  and  the  ala  of  the  thyroid  cartilage. 
The  rima  glottidis  is  the  fissure  formed  anteriorly  by  the 
true  vocal  cords  (glottis  vocalis),  and  posteriorly  by  the 
bases  and  vocal  processes  of  the  arytenoids  (glottis  respira- 
toria).  It  is  the  narrowest  part  of  the  larynx,  being  about 


126  SURGICAL  ANATOMY 

J  inch  at  its  widest  part,  and  is  nearly  i  inch  long  antero- 
posteriorly.  It  is  situated  rather  below  the  centre  of  the 
cavity,  and  forms  the  communication  between  the  middle 
and  lower  compartments  of  the  larynx.  In  making  a  laryngo- 
scopic  examination,  the  tongue  is  pulled  forwards  and  down- 
wards, and  the  warmed  mirror  is  introduced,  pushing  the 
soft  palate  upwards  and  backwards.  Light  from  the  fore- 
head mirror  having  been  thrown  on  it,  the  base  of  the  tongue, 
epiglottis,  and  glosso-epiglottic  folds  are  seen  with  the  valle- 
cula  on  either  side  of  the  median  glosso-epiglottic  fold  (in 
which  may  lodge  a  foreign  body) .  Then  the  aryteno-epiglottic 
folds,  presenting  posteriorly  the  elevations  due  to  the  cunei- 
form cartilages  externally,  and  those  of  Santorini  internally, 
are  seen.  The  false  cords  appear  fairly  wide  apart,  and  of 
a  pink  colour,  while  the  true  cords  project  inwards  toward 
one  another,  are  of  a  pearly-white  colour,  and  are  wide  apart 
when  the  patient  says  '  ah/  and  close  together  when  he  says 
'  ee.'  Between  the  false  and  true  cords  a  dark  interval 
indicates  the  entrance  to  the  ventricle.  When  the  glottis  is 
wide  open,  it  is  sometimes  possible  to  see  as  far  as  the  bifurca- 
tion of  the  trachea. 

The  THYROID  CARTILAGE  is  composed  of  hyaline  cartilage, 
but  begins  to  ossify  about  the  twentieth  year  near  the  crico- 
thyroid  joint.  As  ossification  progresses  with  age,  the 
cartilage  becomes  brittle,  and  may  occasionally  be  fractured 
in  old  persons  by  violence,  such  as  throttling,  a  vertical 
median  fracture  generally  resulting,  which  may  be  accom- 
panied by  displacement  inwards  of  the  fragments,  swelling  of 
the  mucous  membrane,  and  consequent  asphyxia.  The 
operation  of  thyrotomy,  or  median  vertical  incision  of  the 
cartilage,  including  part  of  the  thyro-hyoid  and  crico-thyroid 
membranes,  is  performed  with  the  object  of  removing  foreign 
bodies  in  the  larynx,  or  tumours  of  the  cord,  etc.  Laryngotomy 
is  performed  by  making  a  vertical  incision  through  the  soft 
parts  from  the  middle  of  the  thyroid  to  the  lower  border  of 
the  cricoid,  and  then  incising  the  crico-thyroid  membrane 
transversely  close  to  the  cricoid,  so  as  to  avoid  the  small 
crico-thyroid  vessels.  This  operation  is  sometimes  performed 
where  the  patient  is  being  choked  by  some  foreign  body 
lodged  in  the  larynx.  It  does  not  afford  much  room,  and  is 
above  the  level  at  which  the  membrane  is  often  formed  in 


THE  NECK  127 

diphtheria.  The  larynx  has  occasionally  been  extirpated 
successfully  in  cases  of  malignant  disease  (a  preliminary  low 
tracheotomy  having  been  generally  performed)  through  a 
vertical  incision  from  the  hyoid  to  the  isthmus  of  the  thyroid 
gland,  and  a  transverse  one  at  the  upper  extremity  from  one 
sterno-mastoid  to  the  other.  The  flaps,  consisting  of  skin, 
with  platysma,  deep  fascia,  and  anterior  jugular  veins,  are 
reflected,  as  are  likewise  the  sterno-  and  omo-hyoid  muscles. 
The  sterno-thyroid,  thyro-hyoid,  stylo-  and  palato-pharyngei, 
and  inferior  constrictor  muscles,  and  thyro-hyoid  membrane 
are  divided,  and  the  larynx  set  free  by  separating  the  attach- 
ments of  the  epiglottis  to  the  tongue  and  thyroid  bone.  The 
larynx  is  now  drawn  forward,  the  superior  laryngeal  arteries 
and  internal  laryngeal  nerves  divided,  and  a  careful  separation 
of  larynx  and  pharynx  is  made,  the  connecting  mucous  mem- 
brane being  divided.  Then  the  inferior  laryngeal  arteries  and 
recurrent  laryngeal  nerves  are  divided,  and  the  trachea  is  cut 
across  and  closed,  or  opened  into  the  lower  end  of  the  wound. 
The  trachea  commences  at  the  lower  border  of  the  cricoid 
opposite  the  sixth  cervical  vertebra,  recedes  from  the  surface 
as  it  descends,  being  ij  inches  from  it  at  the  suprasternal 
notch,  and  ends  opposite  the  lower  border  of  the  fourth  dorsal 
by  bifurcating  into  two  bronchi.  The  length  of  the  cervical 
portion  varies  with  the  position  of  the  head,  but  averages 
nearly  3  inches  (about  the  eighth  ring — in  a  child,  from  i  J  to 
2  inches).  It  is  covered  in  front  by  skin,  superficial  tissue, 
anterior  jugular  veins,  deep  fascia,  sterno-hyoid  and  thyroid 
muscles,  thyroid  isthmus  (in  front  of  the  second,  third,  and 
fourth  rings),  and  below  the  isthmus  by  the  thyroidea  ima 
artery,  the  inferior- thyroid  venous  plexus,  and,  at  the  level  of 
the  notch,  by  the  innominate  artery  and  the  left  innominate 
vein,  and  in  children,  and  occasionally  in  adults,  by  the  thymus 
gland.  Posteriorly,  the  trachea  is  in  contact  with  the  oeso- 
phagus, the  sulcus  between  them  being  occupied  by  the  re- 
current laryngeal  nerves,  while  the  lateral  surface  of  the  trachea 
is  compressed  slightly  by  the  lateral  lobes  of  the  thyroid,  and 
below  this  is  in  relation  to  the  common  carotid  arteries. 
The  tissues  surrounding  the  trachea  are  very  lax,  permitting 
fairly  free  movement,  both  vertically  (as  in  swallowing)  and 
laterally.  Thus,  in  performing  tracheotomy,  the  trachea  has 
been  unwittingly  retracted  to  one  side  by  an  assistant,  and  the 


128  SURGICAL  ANATOMY 

oesophagus  exposed.  TRACHEOTOMY  may  be  necessitated  in 
respiratory  obstruction  from  tumours,  foreign  bodies,  or 
diphtheria.  It  may  be  either  high  (above  the  thyroid  isthmus) 
or  low  (below  it).  The  former  is  generally  easier  and  safer, 
owing  to  the  more  superficial  position  of  that  part  and  the 
smaller  number  of  important  structures  in  close  relationship 
to  it,  but  leaves  a  more  prominent  scar.  The  operation  is 
performed  by  placing  a  small  pillow  behind  the  neck  so  as  to 
throw  it  forward,  keeping  the  head  absolutely  straight  and 
steady,  and  then  making  a  vertical  incision  exactly  in  the 
middle  line.  The  skin  and  fasciae  are  cut  through,  the  muscles 
are  separated,  the  thyroid  isthmus  displaced  downwards,  after 
making  two  slight  lateral  cuts  in  the  laryngo-thyroid  suspensory 
fascia,  and  then  a  sharp  hook  is  inserted  into  the  first  ring  of 
the  trachea,  and  an  opening  made  by  cutting  from  below 
upwards  away  from  the  great  vessels.  A  tube  of  suitable 
size  is  then  taken  (not  exceeding  J  inch  in  diameter  under 
eighteen  months,  and  J  inch  in  a  child  under  four  years  of 
age),  and  introduced  like  a  catheter,  with  the  plate  directed 
downwards  toward  the  sternal  notch  and  almost  touching 
the  skin,  so  as  to  present  the  nozzle  vertically  into  the  wound. 
Then,  by  tilting  the  plate  upwards  like  the  handle  of  a  catheter, 
the  point  slides  into  position.  Care  is  required  not  to  intro- 
duce the  point  into  the  cellular  tissue  in  front  of  the  trachea. 
Where  additional  room  is  required,  it  may  be  had  by  cutting 
through  the  cricoid  and  crico-thyroid  membrane,  or  by 
dividing  the  thyroid  isthmus.  The  latter  is  not  in  itself  a 
dangerous  proceeding,  but  large  transverse  vessels  are  not 
infrequently  found  arising  at  the  level  of  the  isthmus.  The 
operation  is  particularly  difficult  in  children,  owing  to  the 
short  fat  neck,  the  closer  relationship  to  vessels,  etc.,  and  the 
softness  and  mobility  of  the  trachea  itself. 

The  THYROID  GLAND  lies  in  front  of  the  trachea  (under  the 
sterno-hyoid  and  thyroid  muscles  and  part  of  the  sterno-mas- 
toids),  and  is  enclosed  in  a  sheath  of  cervical  fascia,  which  con- 
nects it  to  the  lower  part  of  the  larynx  and  upper  part  of  the 
trachea.  Owing  to  this  connection,  the  gland  moves  up  and 
down  with  deglutition,  as,  of  course,  do  most  tumours  of  the 
gland.  It  consists  of  two  lateral  lobes,  of  which  the  right  is 
generally  the  larger,  and  an  isthmus.  The  borders  are  rounded 
on  their  outer  surface,  and  broader  below  than  above.  They 


THE  NECK 


129 


are  about  2  inches  long,  ij  inches  broad,  and  f  inch  thick. 
The  apex  rests  against  the  upper  and  posterior  part  of  the 


28- 


19 


FIG.   14. — DISSECTION  OF  THE  FRONT  OF  THE  NECK. 

(The   area  bounded  on  either  side  by  the  anterior  belly  of  the  digastric 

and  below  by  the  body  of  the  hyoid  bone  is  the  submental  triangle.) 

(From  Buchanan's  "  Anatomy.") 


Anterior  belly  of  digastric.  17. 

Mylo-hyoid.  18. 

Body  of  hyoid  bone.  19. 

Anterior  belly  of  onio-hyoid.  20. 

Sterno-hyoid.  21. 

Thyro-hyoid.  22. 

Isthmus  of  thyroid  cartilage.  23. 

Sterno-thyroid.  24. 

Anterior  belly  of  omo-hyoid.  25. 

Crico-thyroid  membrane.  26. 

Sterno-hyoid.  27. 

Isthmus  of  thyroid  body.  28. 
Inferior  thyroid  plexus  of  veins. 
Clavicular  head  of  sterno-cleido-mastoid.         29. 
Sterno-thyroid. 
Sternal  head  of  sterno-cleido-mastoid. 


Sterno  hyoid. 

Sterno-thyroid. 

Clavicle. 

Subclavian  artery  (third  part). 

Mrachial  plexus. 

Clavicular  head  of  sterno-cleido-mastoid. 

Trapezius. 

Lateral  lobe  of  thyroid  body. 

Cricoid  cartilage. 

Crico-thyroid  muscle. 

Sternal  head  of  sterno-cleido-mastoid. 

Hyo-glossus     muscle     and    hypoglossal 

nerve. 
Posterior  belly  of  digastric  and    stylo- 

hyoid. 


thyroid  cartilage,  and  receives  the  superior  thyroid  vessels  (from 
the  external  carotid).     The  base  is  at  the  level  of  the  sixth  ring 

9 


1 3o  SURGICAL  ANATOMY 

of  the  trachea,  and  receives  at  its  external  border  the  inferior 
thyroid  vessels  from  the  thyroid  axis.  The  blood  is  returned  by 
three  veins — superior,  middle  (to  internal  jugular),  and  inferior 
thyroid  (to  innominate).  The  inner  surface  is  moulded  against 
the  trachea  and  oesophagus  below,  with  the  inferior  laryngeal 
nerve  between  them,  and  the  larynx  and  pharynx  above. 
The  external  rounded  border  is  deeply  grooved  posteriorly 
by  the  common  carotid  artery  (which  frequently  transmits 
pulsation  to  enlargements  of  the  gland),  and  is  in  relation  to 
the  inferior  thyroid  artery,  sympathetic  cord,  and  prevertebral 
muscles.  The  isthmus  lies  about  the  level  of  the  third  tracheal 
ring,  and  in  the  middle  line  is  superficial.  As  the  vascular 
system  of  the  thyroid  does  not  extend  from  side  to  side,  the 
isthmus  may  safely  be  divided  in  the  middle  line.  A  com- 
municating branch  of  the  superior  thyroid  artery  of  either 
side,  however,  frequently  crosses  immediately  above  it,  and 
should  be  avoided.  The  thymus  gland  in  the  child  lies  in 
close  contact  with  its  lower  border,  which  also  is  related  to 
the  inferior  thyroid  veins.  A  small  pyramidal  lobe,  arising 
from  the  upper  border  of  the  isthmus  and  part  of  a  lateral 
lobe,  sometimes  projects  upwards  in  front  of  the  larynx,  being 
attached  at  its  apex  to  the  hyoid  bone  by  a  ligamentous 
structure.  The  gland  is  enervated  by  branches  of  the  cervical 
sympathetic,  which  probably  communicate  in  the  medulla 
with  those  supplying  the  eye,  thus  helping  to  explain  the 
exophthalmos  seen  in  some  forms  of  goitre.  The  lymphatics 
run  to  the  deep  cervical  and  superior  mediastinal  glands. 
The  gland  is  generally  larger  in  females  than  in  males,  and 
may  increase  in  size  during  menstruation.  Pathological 
enlargements  of  the  thyroid  are  generally  called  goitres,  and 
these  are  of  various  types.  They  occur  more  commonly 
in  females,  and  particularly  on  the  right  side.  Such  en- 
largements may  compress  and  cause  deviation  of  the 
trachea,  thus  giving  rise  to  dyspnoea  ;  the  oesophagus,  causing 
dysphagia ;  and  the  recurrent  laryngeal  nerve,  causing 
paralysis  of  the  intrinsic  muscles  of  the  larynx  and  con- 
sequent aphonia.  The  thyroid  vessels  enlarge,  and  are  thin 
walled  ;  the  large  vessels  of  the  neck  are  displaced  laterally, 
and  the  tumour  may  extend  down  beneath  the  sternum 
and  clavicles.  In  cases  of  goitre  a  thyroidectomy ,  or  partial 
excision  of  the  gland,  may  be  performed  through  a  transverse 


THE  NECK  131 

curved  incision  over  the  swelling,  with  the  convexity  down- 
wards/which  extends  through  the  skin,  platysma,  and  deep 
fascia,  including  the  anterior  jugular  veins,  outwards  over 
the  anterior  border  of  the  sterno-mastoid  muscles.  The 
lateral  muscles  and  deep  fasciae  are  now  shelled  laterally 
from  the  capsule  of  the  tumour,  or  divided,  and  the  lateral 
mass  is  projected  forwards,  the  upper  cornu  denned,  and  the 
vessels  ligatured.  Then  the  isthmus  is  divided  in  the  middle 
line,  the  mass  turned  outwards,  and  the  inferior  vessels  liga- 
tured as  far  from  the  larynx  as  possible  to  avoid  injury  to 
the  recurrent  laryngeal  nerve.  If  a  local  anaesthetic  be  used, 
it  is  a  further  safety  to  ask  the  patient  to  say  '  ah  '  while 
ligaturing  these  vessels,  as  the  ability  to  say  this  ensures  that 
the  nerve  is  acting.  The  other  lobe  may  then  be  treated, 
taking  care  to.  leave  in  all  cases  a  portion  of  gland  to  prevent 
occurrence  of  myxcedema. 

Developmentally ,  the  gland  consists  of  three  segments,  the 
middle  being  represented  by  the  isthmus  and  the  pyramidal 
lobe  when  present,  which  latter  communicates  by  the  thyro- 
glossal  duct  with  the  base  of  the  tongue  at  the  foramen 
caecum.  Thyroid  cysts  not  infrequently  arise  in  connection 
with  the  remains  of  this  duct,  and  accessory  lobules  are  some- 
times also  found  in  the  hyoid  region.  The  parathyroid  bodies 
are  two  small  round  masses  found  on  either  side  toward 
the  lower  border  of  the  lateral  lobes. 

The  oesophagus  is  about  10  inches  in  length,  and  commences 
opposite  the  sixth  cervical  vertebra,  pierces  the  diaphragm 
opposite  the  tenth  dorsal  vertebra,  and  immediately  after- 
wards terminates  at  the  cardiac  orifice  of  the  stomach.  The 
cervical  portion  varies  in  length,  like  the  trachea,  with  the 
position  of  the  head.  In  front  of  it  lies  the  trachea,  behind 
it  (and  deep  fascia)  the  prevertebral  muscles.  While  at  its 
commencement  it  is  mesial,  it  soon  deviates  to  the  left,  where 
it  is  more  closely  related  to  the  thyroid  gland,  common 
carotid  artery,  and  recurrent  laryngeal  nerve,  than  on  the 
right.  On  either  side  are  numerous  lymphatic  glands,  which 
drain  this  portion  of  the  oesophagus,  and  are  liable  to  enlarge 
in  carcinomatous  disease,  and  so  cause  pressure  on  the  oeso- 
phagus. Its  lumen  is  compressed  antero-posteriorly.  It  is 
narrow  at  its  commencement  (J  inch),  and  hence  impaction 
of  foreign  bodies  and  acid  burns,  causing  subsequent  cica- 

9—2 


132  SURGICAL  ANATOMY 

tricial  stenosis,  occur  most  generally  at  this  point,  which  is 
situated  about  6  inches  from  the  teeth,  and  is  hence  beyond 
the  reach  of  the  finger.     In  carcinomatous  disease  of  this 
portion  of  the  oesophagus  the  left  recurrent  laryngeal  nerve  is 
often  pressed  on,  and  when  stricture  of  the  tube  results,  a 
left-sided  cesophagotomy  may  be  done  to  relieve  it  (or  to  re- 
move   an    impacted    foreign    body).     An    incision    is    made 
internal  to  the  anterior  margin  of  the  sterno-mastoid  from 
the   thyroid   cartilage   to   the   sterno-clavicular   articulation. 
The  subcutaneous  tissues,  platysma,  anterior  jugular  vein,  and 
deep  fascia,   are  divided,   the  sterno-mastoid  retracted  out- 
wards, the  sterno-hyoid  and  -thyroid  retracted  inwards,  and 
the  omo-hyoid  and  pretracheal  fascia  divided.     The  thyroid 
gland   is   now   drawn   forwards   and   inwards,    the   common 
carotid  outwards,    the   inferior   thyroid   artery  divided,    the 
trachea,  and  the  oesophagus  dilated  by  a  bougie,  recognized, 
and  a  vertical  incision  made  in  the  latter  near  its  vertebral 
aspect,  so  as  to  avoid  the  recurrent  laryngeal  nerve.    Where 
a  portion  is  cut  out  the  operation  is  known  as  cesophagectomy, 
and  where  an  opening  on  to  the  neck  is  established,  ceso- 
phagostomy.     Save  for  the  removal  of  a  foreign  body  or  very 
limited  growth,  a  gastrostomy  is  a  better  operation  as  a  rule. 
The    Carotid    Region. — The    COMMON    CAROTID    ARTERIES 
extend  in  the  neck  from  the  sterno-clavicular  articulation  to 
the  upper  border  of  the  thyroid  cartilage,  a  distance  of  about 
3!  inches.     In  the  lower  part  of  their  course  they  are  placed 
deeply,  and  about  f  inch  apart,  while  in  the  upper  part  they 
are  superficial,  and  about  2  inches  apart.     On  the  right  side 
the  vessel  arises  as  a  terminal  branch  of  the  innominate,  and 
is  in  front  and  to  the  right  of  the  trachea  ;  while  on  the  left 
it  is  given  off  from  the  arch  of  the  aorta,  and  is  more  deeply 
placed,  being  situated  to  the  side  of  the  oesophagus.     The 
vessel  is  enclosed  in  the  carotid  sheath.,  which  is  triangular  in 
section,  and  is  derived  from  the  deep  cervical  fascia.     In  the 
sheath  and  accompanying  the  artery  lies  the  internal  jugular 
vein,  situated  to  the  outside  of  the  artery,   and  the  vagus 
nerve  behind  and  between  the  artery  and  vein.     Within  the 
sheath,  and  closely  associated  with  the  vein,  a  number  of 
small  lymphatic  glands  frequently  exist,  which  are  often  en- 
larged   in    tubercular    disease.     Outside   the   sheath,   on    its 
anterior  surface,  the  descendens  noni  nerve  runs  downwards 


THE  NECK  133 

and  in\yards,  and  numerous  lymphatic  glands  lie  in  this  posi- 
tion, while  posterior  to  the  sheath  the  cervical  sympathetic 
runs.  Other  posterior  relations  are  the  inferior  thyroid  and 
vertebra]  arteries,  prevertebral  fascia  and  muscles,  the  trans- 
verse processes  of  the  cervical  vertebrae,  and,  on  the  right  side, 
the  recurrent  laryngeal  nerve.  On  the  left  side  the  nerve  is 
internal.  Anteriorly,  the  sheath  is  crossed  by  the  omo- 
hyoid  muscle  and  a  branch  of  the  superior  thyroid  artery, 
at  the  level  of  the  sixth  cervical.  The  artery  is  generally 
ligatured  above  this  point,  as  it  is  more  superficial,  being 
overlapped  by  the  sterno-mastoid,  while  below  this  point  it 
is  covered  by  the  sterno-hyoid,  thyroid,  and  mastoid  muscles, 
the  lateral  lobe  of  the  thyroid,  and  thyroid  veins.  This  point, 
therefore,  is  an  important  one  surgically,  and  is  defined  deeply 
by  the  tubercle  on  the  transverse  process  of  the  sixth  cervical 
(Chassaignac's  tubercle),  which  forms  a  reliable  guide  to  the 
artery  in  ligaturing,  and  against  which  the  artery  may  be 
compressed.  The  common  carotid  is  sometimes  affected  by 
aneurism,  which  occurs  generally  at  the  bifurcation,  where 
there  is  normally  a  dilatation,  or  at  the  root  of  the  neck.  The 
pressure  exerted  on  the  surrounding  structures  by  the  tumour 
may  give  rise  to  spasm  of  the  larynx,  and  of  the  diaphragm, 
contracted  pupil  (sympathetic),  oedema,  and  lividity  of  face 
and  arm,  and  anaemia  of  the  brain.  Ligature  of  the  common 
carotid  may  be  performed  for  aneurism  affecting  the  vessel 
itself,  for  aneurism  of  the  innominate  (Wardrop's  operation), 
for  wounds  of  the  vessel,  and  profuse  haemorrhage  from  the  neck 
or  throat  (sarcoma,  etc.).  Where  possible  the  artery  should 
be  ligatured  above  the  omo-hyoid  (seat  of  election).  The 
line  of  the  artery  is  from  the  sterno-clavicular  articulation 
to  a  point  midway  between  the  angle  of  the  jaw  and  the 
mastoid  process,  and  a  3-inch  incision  is  made  along  this  line, 
with  its  centre  opposite  the  cricoid.  The  deep  fascia  is  divided, 
the  sterno-mastoid  drawn  back,  the  omo-hyoid  drawn  down, 
the  sheath  cleared,  opened  on  its  inner  side,  and  the  needle 
passed  from  without  inwards  to  avoid  the  vein,  the  vagus  also 
being  avoided.  The  subsequent  anastomosis  is  between  the 
superior  and  inferior  thyroid  vessels,  branches  of  the  two 
external  carotids,  a  branch  of  the  occipital  of  the  carotid,  and 
the  superior  intercostal  of  the  subclavian  ;  but  is  frequently 
not  sufficient,  notwithstanding  the  circle  of  Willis,  to  keep 


134  SURGICAL  ANATOMY 

the  brain  sufficiently  supplied  with  blood,  syncope  occurring 
at  the  time  of  the  operation,  or  cerebral  softening  some  days 
later. 

The  EXTERNAL  CAROTID  is  the  smaller  terminal  branch, 
and  at  its  commencement  is  in  front  of,  and  to  the  inside  of, 
the  internal.  It  curves  forwards  as  it  ascends,  and  divides 
within  the  parotid  recess  of  the  lower  jaw  into  the  temporal 
and  internal  maxillary  arteries.  It  is  about  2 J  inches  long ; 
passes  beneath  the  digastric  and  stylo-hyoid  muscles ;  is 
separated  from  the  internal  carotid  by  the  stylo-glossus  and 
-pharyngeus  muscles,  stylo-hyoid  ligament,  and  glosso- 
pharyngeal  nerve  and  pharyngeal  branch  of  the  vagus. 
Ligature  of  the  external  is  less  serious  than  that  of  the  common 
carotid,  and  may  be  performed  as  a  preliminary  to  operations 
on  parotid  tumours.  The  artery  is  generally  ligatured  in 
its  first  part,  which  is  below  the  digastric,  and  is  about  I  inch 
long.  An  incision  is  made  in  the  line  of  the  artery  from  the 
angle  of  the  jaw  to  the  upper  border  of  the  thyroid  cartilage 
through  the  skin,  superficial  and  deep  fascia,  the  latter  being 
very  strong  at  this  level,  and  drawing  the  sterno-mastoid  to- 
ward the  angle  of  the  jaw.  The  sterno-mastoid  muscle  and 
the  parotid  gland  are  now  retracted,  and  the  digastric  tendon 
exposed.  The  hypoglossal  nerve,  giving  off  its  descending 
branch,  the  laryngeal  and  facial  veins,  and  one  or  two  lym- 
phatic glands,  lie  in  front  of  the  vessel  ;  while  the  internal 
laryngeal  nerve  lies  behind,  and  the  submaxillary  gland  and 
great  cornu  of  the  hyoid  internally,  the  latter  forming  a 
valuable  guide  to  the  vessel.  The  sheath  is  opened  at  the 
level  of  the  hyoid  cornu,  and  the  needle  passed  from  without 
inwards,  the  internal  laryngeal  nerve  being  avoided.  The 
circulation  is  maintained  by  the  branches  from  either  side 
(facial,  occipital,  etc.)  ;  anastomosis  between  facial  and 
branches  of  the  ophthalmic  (internal  carotid),  and  between  a 
branch  of  the  superior  intercostal  and  of  the  occipital. 

The  INTERNAL  CAROTID  is  the  larger  branch,  and  extends 
within  the  cranium  to  the  anterior  clinoid  process,  where  it 
divides  into  anterior  and  middle  cerebrals.  In  the  carotid 
triangle,  where  it  might  be  ligatured,  it  is  deeper  and  pos- 
terior to  the  external,  and  has  the  same  relations  to  the 
internal  jugular  vein  and  vagus  nerve  as  the  common  carotid. 
It  is  crossed  by  the  occipital  and  posterior  auricular  arteries 


THE  NECK  135 

and  hypoglossal  nerve,  and  is  separated  from  the  external 
carotid  by  the  stylo-glossus  and  pharyngeus  muscles,  stylo- 
hyoid  ligament,  glosso-pharyngeal,  and  pharyngeal  branch  of 
the  vagus  nerves.  The  INTERNAL  JUGULAR  VEIN  begins  in 
the  jugular  fossa  of  the  petrous  as  a  bulb  or  dilatation  at  the 
junction  of  the  lateral  and  inferior  patrosal  sinuses.  At  its 
exit  from  the  skull  it  is  separated  from  the  internal  carotid 
artery  by  the  ninth,  tenth,  and  eleventh  nerves,  and  it  joins 
the  subclavian  vein  behind  the  sterno-clavicular  articulation 
to  form  the  innominate.  The  internal  jugular  vein  is  occa- 
sionally in  danger  of  wounding  in  operations  for  extensive 
tubercular  disease  of  the  glands  of  the  neck.  During  inspira- 
tion the  vessel  is  collapsed,  and  looks  like  connective  tissue, 
while  during  expiration  it  may  become  greatly  distended. 
In  such  cases  the  danger  from  hemorrhage  is  not  so  great  as 
that  from  air  embolism,  air  being  sucked  in  through  the  wound 
in  inspiration,  and  leading  to  embolism  of  the  coronary 
arteries,  etc.  The  connection  of  the  vein  with  tubercular 
glands  has  already  been  referred  to.  It  is  frequently  affected 
by  thrombosis  extending  from  the  sigmoid,  and  becomes  tender 
and  palpable  as  a  thickened  cord  in  the  neck.  Where,  as 
generally  happens,  the  clot  is  septic,  infection  is  very  apt  to 
be  carried  to  the  lungs,  or  sometimes  to  other  parts  of  the 
body. 

The  posterior  triangle  of  the  neck  is  bounded  in  front  by 
the  posterior  border  of  the  sterno-mastoid,  behind  by  the 
anterior  border  of  the  trapezius,  and  below  by  the  clavicle, 
beneath  which  and  between  it  and  the  first  rib  it  communicates 
with  the  axilla.  Superficially,  branches  of  the  cervical 
plexus,  the  external  jugular  vein,  and  some  lymphatic  glands 
are  found.  The  omo-hyoid  lies  a  little  deeper,  and  divides 
the  triangle  into  two,  the  lower  or  SUBCLAVIAN  being  bounded 
in  front  by  the  sterno-mastoid  and — -deeper — the  scalenus 
anticus,  below  by  the  clavicle  and  subclavius,  and  above  and 
behind  by  the  omo-hyoid.  The  pretracheal  fascia,  which  en- 
sheaths  the  omo-hyoid,  is  continued  down  to  the  clavicle,  to 
which,  together  with  the  sheath  of  the  subclavius  and  of  the 
subclavian  vein,  it  is  attached,  and  sometimes  binds  the 
omo-hyoid  so  closely  to  the  .clavicle  as  almost  to  obliterate  the 
subclavian  triangle.  Under  this  fascia  lies  a  chain  of  lym- 
phatic glands,  which  communicate  with  the  mediastinum, 


136  SURGICAL  ANATOMY 

axilla,  and  deep  parts  of  the  neck,  and  the  suprascapular  and 
transversalis  colli  arteries  cross  the  triangle,  the  former 
behind  the  clavicle  and  the  latter  behind  the  omo-hyoid.  This 
triangle  is  of  importance,  as  the  SUBCLAVIAN  ARTERY  in  its 
third  stage  is  ligatured  in  it  for  axillary  aneurism,  wounds,  etc., 
by  an  incision  made  along  the  clavicle,  the  skin  having  pre- 
viously been  pulled  down.  The  skin  is  then  pulled  up,  and 
the  incision  deepened  until  the  triangle  is  exposed.  The 
anterior  scalene  is  made  out,  the  artery  lying  behind  it  and  the 
vein  in  front  of  it,  and  the  finger  is  run  down  its  external 
border  till  it  rests  at  its  insertion  on  the  scalene  tubercule 
(tubercle  of  Lisfranc)  of  the  first  rib,  which  is  the  guide  to 
the  artery.  The  height  of  the  artery  above  the  clavicle 
varies  greatly  in  different  individuals,  and  in  different  posi- 
tions, occasionally  being  so  prominent  as  to  suggest  the 
presence  of  an  aneurism.  The  best  position  for  ligature  is 
with  the  shoulder  depressed  and  the  arm  thrown  behind  the 
back,  while  the  head  is  turned  to  the  opposite  side.  The 
needle  is  passed  from  above  downwards  and  backwards, 
taking  care  not  to  confuse  a  cord  of  the  brachial  plexus  or 
the  omo-hyoid  muscle  for  the  artery — mistakes  which  are 
frequently  made  in  operations  on  the  cadaver.  When  the 
posterior  scapular  artery  presents  in  the  wound,  it  is  better 
to  ligature  it  also,  lest  secondary  haemorrhage  occur.  The 
collateral  circulation  is  by  suprascapular  and  posterior  scapular, 
with  acromio- thoracic,  subscapular,  and  dorsalis  scapulae  ; 
and  superior  and  aortic  intercostals  and  internal  maxillary, 
with  long  thoracic  and  scapular  arteries.  The  PLEURA  lies 
close  to  the  subclavian  artery,  and,  indeed,  the  apex  of  the 
lung  extends  some  J  inch  above  the  clavicle,  behind  the 
sterno-mastoid,  particularly  on  the  right  side.  Thus  injury 
to  the  pleura  may  result  from  ligature  of  the  artery,  or  re- 
moval of  a  tumour  or  adherent  tubercular  glands,  while  it 
also  has  been  injured  by  stabs  in  the  neck,  severe  fracture  of 
the  clavicle,  etc.  The  lung  may  occasionally  produce  an 
appreciable  swelling  in  the  neck  during  severe  coughing. 

The  portion  of  the  posterior  triangle  which  lies  above  the 
omo-hyoid  is  known  as  the  OCCIPITAL  TRIANGLE.  It  is  bounded 
in  front  by  the  posterior  border  of  the  sterno-mastoid,  behind 
by  the  anterior  border  of  the  trapezius,  and  below  by  the 
omo-hyoid.  The  floor  is  formed  from  above  downwards  by 


THE  NECK  137 

the  snlenius  capitis,  levator  anguli  scapulae,  and  scalenus 
medius  and  posticus.  Superficially  it  is  covered  by  the  skin 
and  fascia,  with  platysma  in  the  lower  portion,  and  presents 
superficial  branches  of  the  cervical  plexuc — namely,  lesser 
occipital,  great  auricular,  transverse  cervical  (all  emerging 
from  posterior  border  of  sterno-mastoid) ,  and  supraclavicular 
branches  (in  lower  part  of  the  triangle).  Lying  deeply  along 
the  posterior  border  of  the  sterno-mastoid  are  the  glandule? 
concatenates. 

The  anterior  portion  of  the  neck  is  formed  embryonically 
by  the  growing  forward  of  five  branchial  arches,  with  clefts — 
or,  in  the  human  embryo,  grooves — both  external  and  internal 
(called  '  recesses  '),  between  them.  The  first  arch  forms  the 
lower  jaw  and  malleus.  The  second,  or  hyoid  arch,  which 
forms  the  incus,  styloid  process,  and  part  of  the  hyoid,  grows 
rapidly,  and,  as  flexion  of  the  neck  occurs  at  this  period,  soon 
overlaps  the  other  arches,  which  become  buried,  and  ulti- 
mately lose  their  epiblast.  A  cervical  fistula  leading  down 
to  these  arches  persists  for  a  time,  however,  and  in  some 
cases  permanently,  as  a  fine  channel,  with  small  opening  a 
little  above  the  sterno-clavicular  articulation,  which  pene- 
trates a  varying  distance.  Various  forms  of  cysts,  also,  with 
epithelial  lining,  may  arise  from  the  included  epiblast  of  these 
buried  arches,  and  are  sometimes  alluded  to  as  hygromas, 
or  hydroceles  of  the  neck,  and  occur  most  frequently  in  the 
posterior  triangle.  The  first  external  groove  forms  the 
external  auditory  meatus,  the  membrane  between  it  and  the 
internal  groove  forming  the  tympanic  membrane.  The 
internal  grooves  between  the  arches  disappear  early,  with  the 
exception  of  the  first,  which  persist  as  the  tympanic  Eus- 
tachian  passage.  The  second  leaves  traces  in  the  fossa  of 
Rosenmiiller  in  the  pharynx  and  the  supratonsillar  fossa,  and 
the  fourth  in  the  pyriform  fossa  at  the  pharyngo-laryngeal 
junction.  Cervical  ribs  occasionally  occur,  especially  in  con- 
nection with  the  seventh  cervical  vertebra — sometimes  anchy- 
losed  to  the  transverse  process,  and  sometimes  movable  ; 
sometimes  short  and  resembling  an  exostosis,  at  others  long 
and  well  formed.  In  the  latter  case  the  subclavian  artery 
passes  over  the  rib,  and  so  projects,  simulating  aneurism, 
and  the  scalene  muscles  may  be  attached  to  it.  Even  the 
smaller  forms  may,  however,  present  a  projection  in  the  neck 


138  SURGICAL  ANATOMY 

if  the  subject  be  thin,  and  they  sometimes  give  rise  to  trouble 
from  pressure  on  the  cords  of  the  brachial  plexus. 

The  neck  communicates  with  the  thorax  anteriorly,  many 
of  the  structures  passing  directly  from  the  one  to  the  other. 
On  the  right  side  the  innominate  vessels  are  comparatively 
superficial,  and  the  vagus  nerve  passes  down  in  front  of  the 
subclavian  artery.  On  the  left  side  the  separate  carotid  and 
subclavian  are  much  deeper,  and  the  vagus  passes  down 
between  them.  The  INNOMINATE  artery  is  about  ij  inches 
long,  and  extends  up  and  outwards  to  the  sterno-clavicular 
articulation,  where  it  divides,  being  at  first  in  front  of  the 
trachea,  and  then  to  its  outer  side.  In  front  of  the  vessel 
are  the  left  innominate  and  inferior  thyroid  veins.  To  its 
right  side  are  the  right  innominate  vein,  vagus  nerve,  and, 
pleura,  while  to  its  left  are  the  left  cornu  of  hyoid,  carotid 
artery,  and  trachea.  It  is  occasionally  affected  by  aneurism, 
causing  dyspnoea,  cough  from  pressure  on  the  recurrent 
laryngeal,  difficulty  in  swallowing,  etc.  The  condition  is  best 
treated  by  needling,  but  ligature  has  been  done  through  an 
incision  along  the  lower  end  of  the  anterior  border  of  the 
sterno-mastoid,  and  then  out  along  the  inner  one-third  of 
the  clavicle,  cutting  the  sterno-mastoid,  hyoid,  and  thyroid 
muscles,  and  the  anterior  jugular  vein.  Collateral  circulation 
would  take  place  by  the  superior  with  aortic  intercostals  ; 
internal  maxillary  with  deep  epigastric  and  aortic  intercostals  ; 
circle  of  Willis,  etc.  Between  the  sterno-mastoid  and  the 
scalenus  anticus  lie  the  phrenic  nerve,  omo -hyoid  muscle, 
transversalis  colli,  and  suprascapular  arteries,  external  jugular, 
and  subclavian  veins.  Behind  the  scalenus  anticus,  and  be- 
tween it  and  the  other  scalenes,  pass  the  subclavian  artery 
and  cords  of  the  brachial  plexus.  The  SUBCLAVIAN  ARTERY 
arises  from  the  innominate  on  the  right  and  the  aorta  on  the 
left,  and  reaches  the  inner  border  of  the  scalenus  anticus  in 
its  first  stage,  passes  behind  the  muscle  in  its  second,  and  in 
its  third  extends  to  the  outer  border  of  the  first  rib,  beyond 
which  point  it  is  known  as  the  axillary.  The  first  stage, 
therefore,  differs  considerably  on  the  two  sides.  On  the  left 
it  is  larger,  deeper,  and  more  vertical  ;  the  internal  jugular 
vein  and  vagus  nerve  run  parallel  instead  of  crossing  it  at 
right  angles  ;  the  recurrent  laryngeal  nerve  lies  to  the  inner 
side,  instead  of  looping  round  the  deep  aspect  ;  and  the 


THE  NECK  139 

oesophagus  and  thoracic  duct  only  form  relations  on  this 
side.  In  its  first  stage  it  gives  off  (i)  the  vertebral  artery, 
which  ascends  between  the  scalenus  anticus  and  longus  colli 
to  the  foramen  in  the  transverse  process  of  the  sixth  cervical. 
It  has  been  ligatured  in  some  cases  of  epilepsy  by  an  incision 
along  the  posterior  border  of  the  sterno-mastoid,  just  above 
the  clavicle,  the  carotid  tubercle  of  the  transverse  process  of 
the  sixth  cervical  forming  a  guide.  This  vessel  is  surrounded 
by  vaso-motor  nerves  from  the  inferior  cervical  ganglion, 
and  higher  up  is  in  close  connection  with  the  hypoglossal  and 
suboccipital  nerves.  (2)  The  internal  mammary,  which  origi- 
nates at  the  inner  border  of  the  scalenus  anticus,  and  passes 
down  behind  the  first  costal  cartilage  to  the  thorax,  where  it 
runs  parallel  to  and  \  inch  from  the  sternal  border.  It  may 
be  wounded,  and  give  rise  to  fatal  haemorrhage,  and  is  most 
easily  treated  through  the  second  intercostal  space.  (3)  The 
thyroid  axis,  which  arises  opposite  the  internal  mammary,  and 
divides  into  inferior  thyroid,  suprascapular,  and  transversalis 
colli.  (4)  The  superior  intercostal  arises  from  either  first  or 
second  stage,  passes  upwards  and  backwards  over  the  pleura, 
and  then  descends  into  the  thorax  in  front  of  the  neck  of 
the  first  rib,  and  supplies  the  first  two  intercostal  spaces.  It 
anastomoses  with  a  branch  of  the  occipital.  The  subclavian 
is  occasionally  affected  by  aneurism,  especially  on  the  right 
side,  in  its  third  part,  forming  a  pulsating  tumour  in  the 
posterior  triangle,  and,  as  it  increases,  produces  pressure  symp- 
toms, including  spasm  of  the  diaphragm  from  pressure  on  the 
phrenic  nerve.  When  it  is  necessary  to  ligature  the  vessel, 
this  should,  where  possible,  be  done  in  the  third  part,  as 
already  described.  Ligature  of  the  first  part  is  difficult  and 
dangerous. 


THE  VERTEBRAL  COLUMN 

The  vertebral  column  supports  the  head,  connects  the 
upper  and  lower  segments  of  the  trunk,  gives  attachment  to 
the  ribs,  is  extremely  flexible,  and  contains  and  protects  the 
spinal  cord. 


140  SURGICAL  ANATOMY 

The  spinous  processes  projecting  behind,  and  the  trans- 
verse processes  projecting  laterally,  form  two  deep  vertical 
grooves,  which  lodge  the  powerful  muscles  which  support  and 
control  the  movements  of  the  column.  In  the  adult  the 
column  presents  four  curves — two  primary,  thoracic  and 
sacral,  which  are  also  present  in  the  fcetus,  are  due  to  the 
shape  of  the  bones,  and  whose  concavity  is  directed  forwards  ; 
and  two  secondary,  cervical  and  lumbar,  which  are  acquired 
after  the  assumption  of  the  erect  posture,  are  due  to  the  shape 
of  the  intervertebral  discs,  and  whose  convexity  is  directed 
forwards.  In  infancy,  prior  to  the  formation  of  the  secondary 
curves,  the  spine  generally  presents  a  slight  general  backward 
convexity,  which  in  rickety  children  may  proceed  to  form  a 
pronounced  KYPHOSIS.  In  old  persons,  in  whom  the  discs 
have  atrophied,  the  spine  frequently  assumes  a  slight  general 
backward  convexity  ;  and  in  cases  of  rheumatoid  arthritis 
affecting  the  spine  the  various  joints  may  become  fused, 
producing  a  rigid  spine,  which  is  frequently  fixed  in  a  kyphotic 
curve.  As  the  spines  of  the  vertebrae  vary  in  length,  a  line 
joining  them  would  not  repeat  the  curves  of  the  column. 
The  junction  of  the  fifth  lumbar  vertebra  with  the  sacrum 
forms  a  marked  projection — the  s aero -vertebral  angle — which 
is  frequently  felt  in  abdominal  palpation.  Sometimes  the 
lumbar  vertebrae  slip  forward  from  the  sacrum  at  this  point, 
owing  to  defective  development  of  the  last  lumbar  vertebra, 
producing  spondylolisthesis.  Even  normally  a  slight  lateral 
curve  of  the  spine  in  the  dorsal  region,  with  the  convexity 
toward  the  right,  and  compensatory  curves  above  and  below 
with  the  convexity  to  the  left,  may  be  present.  This  lateral 
curve  has  been  attributed  to  the  greater  use  of  the  right 
arm,  and  to  the  pressure  of  the  thoracic  aorta  on  the  dorsal 
vertebrae. 

SCOLIOSIS  consists  of  an  exaggeration  of  this  lateral  curve, 
the  convexity  of  the  curve  being  generally  to  the  right,  while 
the  vertebrae  rotate,  so  that  their  bodies  are  directed  to  the 
convexity  of  the  curve.  The  ribs  move  with  the  vertebrae, 
and  thus  the  angles  of  the  ribs  on  the  side  of  the  convexity  are 
prominent,  and  make  the  angle  of  the  scapula  project,  while 
on  the  concave  side  they  are  depressed.  Correspondingly,  the 
front  of  the  chest  on  the  side  of  the  convexity  is  flattened,  while 
it  is  prominent  on  the  concave  side.  The  ribs  are  also 


THE   VERTEBRAL  COLUMN  141 

separated  from  one  another  on  the  convex  side,  and  hence  the 
shoulder  is  raised,  while  they  are  crowded  together  on  the 
concave  side,  the  shoulder  being  depressed.  The  condition 
is  due  to  loss  of  tone  of  the  muscles  (erector  spinae  attached  to 
the  transverse  processes  and  ribs,  and  the  multifidus  spinae, 
etc.,  to  the  spinous  processes)  and  ligaments,  and  is  frequently 
associated  with  flat-foot,  which  is  due  to  a  similar  condition, 
and  is  frequently  an  exciting  cause. 

The  VERTEBRAL  DISCS,  twenty-three  in  number,  make  up 
nearly  one-quarter  of  the  length  of  the  spine,  act  as  buffers 
and  springs,  form  the  cervical  and  lumbar  curves,  and  assist 
in  the  formation  of  the  intercentral  articulations.  These  are 
amphiarthrodial  joints,  and  while  the  movement  permitted 
in  each  individually  is  slight,  the  spine  as  a  whole  is  capable 
of  very  considerable  movement,  particularly  in  the  cervical 
and  lumbar  regions,  where  not  only  antero-posterior  but 
lateral  and  rotatory  movements  are  possible. 

LORDOSIS,  or  an  exaggeration  of  the  normal  lumbar  curve, 
with  the  convexity  forwards,  is  frequently  seen  in  hip  disease, 
where  all  the  movement  permitted  in  the  limb  may  be  derived 
from  the  lumbar  spine,  and  not  from  the  hip-joint. 

The  BODIES  of  the  vertebrae  are  the  most  frequent  site  of 
tubercle  of  bone.  Generally  two  contiguous  bodies  are 
affected,  the  pus  escaping  anteriorly  between  the  ligaments 
to  form  a  psoas  or  other  abscess  (according  to  the  position — 
retro-pharyngeal  in  the  cervical  region,  psoas  in  the  dorsal 
or  upper  lumbar),  and  the  bodies  collapsing,  forming  an 
angular  projection  or  '  curvature  '  of  the  spine,  known  as 
POTT'S  DISEASE.  The  bodies  of  the  vertebrae  are  also 
markedly  eroded  -by  the  pressure  of  thoracic  aneurism, 
whereas  the  intervertebral  discs  are  comparatively  resistant 
to  such  pressure. 

SPRAINS  of  the  column  are  generally  produced  by  indirect 
violence,  and  occur  most  frequently  in  the  cervical  and  lumbar 
regions,  owing  to  the  mobility  of  these  parts,  and  their 
proximity  to  the  head  and  pelvis  respectively.  Sprained 
back  frequently  causes  pain  and  inconvenience  to  a  patient 
for  a  considerable  time  after  an  injury,  owing,  perhaps,  in 
some  cases  to  implication  of  some  of  the  spinal  joints,  and  in 
others  to  damage  to  the  muscles.  The  condition  may  be 
simulated  in  rheumatic  affections  of  the  muscles — lumbago — 


142  SURGICAL  ANATOMY 

and  is  one  which  causes  considerable  difficulty  in  medico- 
legal  work.  Sprains  are  seldom  associated  with  much  destruc- 
tion of  the  parts,  a  fracture  dislocation  generally  occurring 
in  such  cases. 

Most  of  the  severe  damages  met  with  in  the  vertebral 
column  from  injury  are  of  the  nature  of  FRACTURE  DISLOCA- 
TIONS, the  contained  cord  adding  greatly  to  the  gravity  of 
the  condition.  The  cord,  however,  occupies  a  neutral  position 
between  the  bodies  and  the  spines,  and  thus  frequently 
escapes,  unless  an  actual  displacement  of  one  or  more  verte- 
brae occurs.  While  fracture  can  occur  without  dislocation, 
dislocation  very  rarely  occurs  without  fracture,  except  in 
the  case  of  the  first,  second,  and  fifth  cervical  vertebrae,  and 
of  the  lumbo-sacral  articulation. 

Fracture  dislocations  may  be  caused  by  either  direct  or 
indirect  violence.  The  latter  are  by  far  the  more  common, 
and  are  generally  due  to  violent  forced  flexion  of  the  spine, 
the  injury  occurring  about  the  junction  of  a  flexible  and  a  rigid 
portion  of  the  column,  as  at  the  cervico-dorsal  (frequently 
between  the  fifth  and  seventh  cervical)  from  falls  on  the  head, 
or  dorso-lumbar  from  weights  falling  on  the  shoulders.  Owing 
to  the  forward  flexion,  the  broad  vertebral  bodies  tend  to  be 
crushed  together,  and  the  narrow  tough  laminae  and  spines,  with 
their  strong  ligaments,  tend  to  be  torn  apart,  while  the  cord 
lies  in  comparative  security  between  these  two  forces.  As  a 
rule,  the  upper  body  is  displaced  down  and  forwards,  complete 
dislocation  being  prevented  by  locking  of  the  posterior  pro- 
cesses. The  affected  vertebral  bodies  are  partially  crushed, 
and  the  intervertebral  discs  lacerated,  as  likewise  the  anterior 
and  posterior  common  ligaments  in  more  severe  cases.  The 
laminae,  or  spines,  are  broken,  and  the  supra-  and  interspinous 
and  capsular  ligaments  and  ligamenta  subflava  torn.  The 
articular  processes  are  generally  broken  in  the  dorsal  region, 
but  escape  in  the  cervical  and  lumbar  regions.  Replacement 
by  forcible  extension  and  manipulation  is  frequently  suc- 
cessful, although  perhaps  most  difficult  in  the  lumbai 
region. 

Direct  violence  may  produce  an  injury  at  any  part  of  the 
spine,  the  mechanism  of  the  indirect  form  being  reversed. 
A  blow  on  the  back  tends  to  crush  the  posterior  segment,  and 
to  tear  the  bodies  in  front  apart ;  much  displacement  is  un- 


THE   VERTEBRAL  COLUMN  143 

common,  and  the  cord,  therefore,  more  frequently  escapes. 
The  occipital  bone  has  been  dislocated  from  the  atlas,  and 
more  commonly,  as  in  hanging,  the  atlas  has  been  dislocated 
forwards  from  the  axis,  the  odontoid  process  being  broken. 
The  spinous  processes  of  the  lower  cervical  and  dorsal  regions 
may  be  broken  off  by  direct  violence.  Where  injuries  to  the 
column  cause  pressure  upon  the  spine,  it  may  be  necessary 
to  perform  a  laminectomy  for  its  relief  (q.v.). 

THE  CORD 

In  the  adult  the  cord  is  generally  about  18  inches  long, 
extending  from  the  foramen  magnum  to  the  lower  border  of 
the  body  of  the  first  lumbar  vertebra.  It  sometimes  ends 
about  the  depth  of  a  vertebral  body  above  or  below  this 
point,  and  in  flexion  it  is  raised  about  f  inch.  At  the  fora- 
men magnum  it  becomes  continuous  with  the  medulla,  while 
below  it  tapers  to  a  point — the  conus  medullaris — from  which 
the  filum  terminate,  composed  of  pia  mater,  containing  in  its 
upper  half  nerve  elements  and  continuation  of  central  canal 
of  the  cord,  is  prolonged  to  the  back  of  the  coccyx,  running 
down  amidst  the  cords  of  the  upper  sacral  nerves,  to  which 
the  term  cauda  equina  is  applied.  The  spinal  meninges 
extend  to  the  second  piece  of  the  sacrum,  and  thence  form  a 
closed  cover  for  the  filum  terminale.  The  third  sacral  spine, 
therefore,  marks  the  lowest  level  to  which  cerebro-spinal 
fluid  may  descend  in  the  spinal  canal.  In  early  foetal  life 
the  cord  occupies  the  whole  canal,  and  at  birth  it  reaches  the 
third  lumbar  vertebra.  The  cervical  enlargement  is  most 
prominent  opposite  "the  sixth  cervical,  and  the  dorsal  enlarge- 
ment opposite  the  twelfth  dorsal.  The  former  measures  about 
J  inch  from  side  to  side,  and  the  latter  slightly  less.  The 
space  between  the  spinal  dura  and  the  bone  is  occupied  by 
loose  areolar  tissue,  containing  a  VENOUS  PLEXUS.  These 
veins  communicate  through  the  ligamenta  subflava  with  the 
dorsal  spinal  veins,  which  receive  blood  from  the  integument 
and  muscles  of  the  back,  and  thus  a  thrombosis,  or  even 
meningitis,  may  spread  inwards  from  deep  external  septic 
processes.  Extensive  haemorrhage  may  result  from  injury 
involving  these  veins,  the  blood  gravitating  toward  the  lower 
end  of  the  canal,  and  occasionally  causing  pressure. 


144 


SURGICAL  ANATOMY 


The  DURA,  continuous  with  that  of  the  medulla,  is  strong 
and  tough,  and  but  loosely  attached  to  the  bone.  The 
ARACHNOID  is  closely  attached  to  the  dura,  the  subdural  space 
being  practically  only  potential,  while  the  subarachnoid  space 
is  extensive  and  continuous  with  that  of  the  brain,  whence 
inflammatory  conditions  (meningitis)  and  effusions  of  blood 


...i 


FIG.  15. — THE  TERMINAL  PART  OF  THE  SPINAL  CORP,  ANP  THE 

CAUDA  EQUINA. 
(From  Buchanan's  "  Anatomy.") 


1.  Linea  splendens. 

2.  Cauda  equina. 


3.  Conns  medullaris. 

4.  Filum  terminals. 


may  readily  extend.  Great  increase  in  pressure  may  arise 
in  meningitis,  and  may  be  relieved  by  LUMBAR  PUNCTURE,  the 
same  procedure  being  adopted  for  obtaining  specimens  of 
cerebro-spinal  fluid  for  investigation  in  certain  diseases,  while 
spinal  anaesthesia  is  produced  by  injecting  local  anaesthetics 
into  the  spine  by  a  similar  puncture.  The  needle  is  intro- 
duced a  little  to  the  side  of  the  spinous  processes,  on  a  level 


THE   VERTEBRAL  COLUMN  145 

with  the  iliac  crests,  up  and  inwards  between  two  of  the  pro- 
cesses (third  to  fifth  lumbar),  the  ligamenta  subflava  between 
two  laminae  being  perforated,  until  the  subarachnoid  space 
is  reached,  the  patient  meanwhile  bending  forward.  The 
needle  enters  the  membranes  below  the  termination  of  the 
cord,  which  is  thus  safe  from  injury.  Normally  the  cerebro- 
spinal  fluid  contains  0-05  per  cent,  of  albumin,  and  is  under 
slight  pressure.  If  the  pressure  be  much  reduced,  convulsions 
may  follow,  as  is  seen  in  some  cases  of  spina  bifida,  with 
extensive  leakage  of  fluid. 

The  PIA  MATER  closely  envelopes  the  cord  and  in  it  ramify 
the  VESSELS  supplying  the  cord,  which  are  derived  from  the 
vertebral,  intercostal,  lumbar,  ilio-lumbar,  and  lateral  sacral 
arteries.  Both  dura  and  pia  send  prolongations  along  the 
nerve  cords  leaving  the  spine,  which  in  the  case  of  the  larger 
plexuses  extend  a  considerable  distance. 

SPINA  BIFIDA  is  a  congenital  malformation  of  the  cord 
or  its  membranes,  associated,  as  a  rule,  with  defect  in  the 
union  of  the  laminae  of  one  or  more  vertebrae.  The  most 
common  form  is  said  to  be  the  myelocele,  in  which  the  central 
canal  of  the  cord  opens  on  to  a  shallow  depression  on  the 
skin  surface.  As  the  cerebro-spinal  fluid  escapes  freely  from 
the  aperture,  death  generally  occurs  early.  The  central 
canal  of  the  cord  may  dilate  and  form  a  protrusion  of  cord 
and  membranes,  known  as  a  syringo-myelocele.  Meningo- 
myelocele  is  the  most  common  form  which  survives,  and  con- 
sists of  a  protrusion  of  membranes  and  cord,  the  latter  lying 
as  a  flattened  band  on  the  posterior  wall  of  the  cyst.  Where 
the  membranes  alone  are  protruded  the  condition  is  known 
as  meningocele,  and -where  there  is  a  defect  in  the  vertebral 
arches,  but  no  protrusion  of  membranes  or  cord,  the  condition 
is  known  as  spina  bifida  occulta.  Spina  bifida  generally 
affects  the  lumbar  region,  but  may  occasionally  occur  in  the 
cervical,  and  very  rarely  in  the  dorsal. 

The  cord  lies  free  within  its  sheath,  suspended  in  its  position 
by  the  various  nerve  roots  which  it  gives  off,  and  surrounded 
by  the  arachnoid  water-bed. 

CONCUSSION  OF  THE  CORD  may  arise  from  severe  shaking, 
giving  rise  to  molecular  changes  in  the  cord  substance,  which 
may  result,  generally  after  some  time  has  elapsed,  in  serious 
consequences. 

10 


146  SURGICAL  ANATOMY 

WOUNDS  of  the  cord,  without  accompanying  fracture  ol 
the  column,  are  uncommon,  save  between  the  occiput,  atlas, 
and  axis,  unless  the  wound  be  made  to  correspond  with  the 
inclination  of  the  spines  and  laminae,  as  in  lumbar  puncture. 

CRUSHING  OF  THE  CORD  is  generally  associated  with  a  lesion 
of  the  column,  which  may  either  be  due  to  trauma  or  to  disease. 
In  the  case  of  trauma,  fracture  dislocation  is  the  most  common 
cause,  the  lesion  generally  affecting  the  upper  portion  of  the 
cord.  Thus  in  the  atlo-axoid  region  death  frequently  results, 
as  in  hanging,  while  severe  injury  to  the  cord  often  accom- 
panies damage  to  the  cervico -dorsal  region,  owing  to  the 
mobility  of  the  spine  and  small  size  of  the  bodies  permitting 
of  considerable  displacement.  In  the  lower  dorsal  region 
displacement  is  less  likely  to  occur,  but  is  generally  pro- 
nounced when  it  does  occur,  while  the  cord  only  extends  to 
the  upper  extremity  of  the  lumbar  region,  where  displace- 
ment is  easily  caused  by  very  severe  injury.  In  traumatic 
cases  the  lesion  is  produced  suddenly,  and,  the  cord  having  no 
time  to  adapt  itself  to  the  pressure,  a  small  lesion  is  likely 
to  produce  graver  results  than  in  chronic  cases.  Chronic 
conditions  may  be  due  to  Pott's  disease,  with  marked  angular 
deformity  ;  less  often  to  extreme  scoliosis,  rheumatoid  arthritis, 
etc.  ;  while  tumours  growing  in  connection  with  the  mem- 
branes similarly  may  cause  pressure  on  the  cord.  It  is  often 
of  importance  surgically  to  be  able  to  DIAGNOSE  THE  SITE  OF 
A  LESION  from  the  symptoms,  where  the  external  evidence  of 
injury  does  not  afford  a  sufficient  guide.  In  this  connection 
it  is  necessary  to  remember  that  the  nerve  trunks  generally 
arise  from  the  cord  some  distance  above  the  POINT  OF  EMER- 
GENCE from  the  canal.  Thus,  while  the  first  and  second 
cervical  run  almost  horizontally  outwards,  the  other  nerves 
gradually  pursue  more  oblique  courses,  until  the  lowest 
trunks  run  almost  vertically  downwards.  The  first  seven 
cervical  nerves  emerge  above  their  corresponding  vertebrae, 
while  the  eighth  emerges  between  the  seventh  cervical  and 
first  dorsal  vertebrae.  The  dorsal,  lumbar,  and  sacral  nerves 
all  emerge  below  their  respective  vertebrae.  The  points  of 
origin  of  the  various  nerves  are  given  in  Fig.  16  (q.v.).  As 
each  nerve  runs  down  within  the  canal  from  its  point  of 
origin  to  its  exit,  a  nerve  belonging  to  a  higher  segment  may 
be  damaged  by  an  injury  at  a  lower  level,  thus  producing 


THE   VERTEBRAL  COLUMN 


147 


Scapular 


st.-mastoid 
Trapezius 

r  Diaphragm 


>  Neck  and  scalp 
Neck  and  shoulder 


'     Hand 
j          (ulna  lowest) 


Intercostal 
.   muscles. 


nt  of  thorax  f  Epigastric 

I    ) 

rEnsiform  area 


Abdomen 
(Umbilicus  toth) 


>  Buttock,  upper 
J  J      part 


I  Groin  and  scrotum 
f     (front) 


Extensors,  knee 
Adductors 


Leg,  inner  side 
Buttock,  lower 
part 


^  Extensors  (?) 
Flexors,  knee  (?) 


Muscles  of  leg 
moving  foot 


Perineal  and  anal 
muscles 


)  Skin  from  coccyx 
I      to  anus. 


FIG.  16. — THE  APPROXIMATE  RELATION  TO  THE  SPINAL  NERVES  OF  THE 
VARIOUS  MOTOR,  SENSORY.  AND  REFLEX  FUNCTIONS  OF  THE  SPINAL 
CORD.  (From  Gowers'  "Nervous  System.") 

10—2 


148  SURGICAL  ANATOMY 

what  might  at  first  appear  to  be  a  mixed  lesion ;  while  some- 
times the  cord  may  escape,  and  the  nerves  alone  be  damaged. 
In  fracture  dislocations  due  to  indirect  violence  the  motor 
columns  generally  suffer  more  than  the  sensory,  and  may 
alone  be  affected.  Loss  of  reflex  action  in  the  part  of  the  body 
supplied  by  the  damaged  segment  generally  points  to  destruc- 
tion of  the  grey  matter  at  that  point,  with  loss  of  the  reflex 
arc.  From  want  of  proper  control,  also,  the  reflexes  below 
the  point  of  lesion  are  generally  exaggerated.  The  effects  of 
lesions  at  various  levels  are  given  in  tabular  form  : 

CERVICAL   i   TO  3  : 

Often  instant  death. 

Complete  paralysis  below  head. 

Asphyxia. 

CERVICAL  3  TO  DORSAL  2  : 

Motor  and  sensory  paralysis,  including  arms  if  above  second 

dorsal. 

Diaphragmatic  breathing  if  below  fourth  or  fifth  cervical  (a). 
Slow  pulse  (6). 
Contracted  pupils. 

Vomiting  and  persistent  hiccough  (b). 
Incontinence  of  urine  and  faeces  (c). 
Priapism. 

DORSAL  2  TO  10  : 

Motor  and  sensory  paralysis  of  abdomen  and  lower  limbs. 
Diaphragm  assisted  by  intercostals  below  sixth  dorsal. 
Incontinence  of  urine  and  faeces  (c). 
Priapism. 

DORSAL  n   AND   12  AND  LUMBAR: 

Incomplete  paraplegia  and  anaesthesia,  with  zone  of  hyper- 

oesthesia. 
Bladder  distended  at  first,  with  subsequent  control  (c). 

(a)  Phrenic  nerve  arises  from  third,  fourth,  and  fifth  cervical,  but 
especially  fourth. 

(b)  Effects  upon  vagus  via  spinal  accessory,  which  is  given  off  about 
sixth  or  seventh  cervical. 

(c)  The  vesical  and  rectal  centres  are  situated  in  the  lumbar  enlarge- 
ment.    Normally,  when  these  visci  become  distended,  a  sensory  impulse 
is  conveyed  to  the  centres  in  the  lumbar  enlargement.     These  centres, 
however,  are  controlled  from  the  brain,  and  hence  cannot  act  without 
volition  on  the  part  of  the  patient.     Where  the  cord  is  damaged  above 
the  centre,   the  inhibitory  fibres  from  the  brain  cannot  control  the 
centre,  which  then   (after  the  first  shock  of  the  accident,  producing 
retention,   has  passed    off)   acts  automatically  without  any  volitional 
control,  emptying  these  visci  when  distended.     If  the  centres  or  the 
nerves  between  them  and  the  bladder  and  rectum  be  damaged,  then 
there  is  complete  loss  of  control,  with  incontinence  of  urine  and  faeces. 


THE   VERTEBRAL  COLUMN  149 

When,  the  cord  is  crushed  by  injury  or  disease,  it  may  be 
necessary  to  perform  a  laminectomy  for  the  relief  of  the  con- 
dition. A  median  incision  is  made  over  the  affected  spines, 
the  muscles  shelled  on  either  side,  the  laminae  of  several 
vertebrae  divided,  and  an  osteo-ligamentous  flap  lifted  up, 
after  cutting  the  supra-  and  interspinous  ligaments  and  liga- 
menta  subflava  between  the  flap  and  the  part  to  be  lifted 
(Macewen).  The  parts  are  then  inspected,  the  cord  being 
cautiously  turned  to  either  side  for  inspection  of  the  under- 
lying structures,  and  then  the  bony  projection  or  tumour 
removed.  The  operation  is  not  likely  to  be  successful,  unless 
the  spinal  pulsation  is  fairly  restored.  It  is  undesirable  to 
open  the  membranes,  unless  the  lesion  be  situated  within  them. 
In  this  manner  pressure  from  dislocations,  angular  curvature, 
tumours,  etc.,  may  be  removed,  and  in  some  cases  the  primary 
focus  in  Pott's  disease  may  thus  be  successfully  eradicated. 
Haemorrhage  is  not  excessive,  and  is  quite  controllable. 


SECTION    II 
THORAX 

THE    THORAX 

THE  SKIN  of  the  chest  is  freely  movable  on  the  underlying 
structures,  owing  to  the  lax  nature  of  the  subcutaneous 
tissues,  which  are  particularly  abundant  over  the  posterior 
and  lateral  regions.  While  the  skin  over  the  front  and  sides 
of  the  chest  is  thin  and  fine,  that  over  the  shoulders  is  thick 
(nearly  J  inch)  and  coarse,  and  contains  many  sebaceous 
glands,  acne  frequently  occurring  in  this  region.  The  shoulders 
are  also  a  favourite  site  for  lipomas,  which  frequently  develop 
in  the  subcutaneous  tissues.  As  a  rule,  the  two  sides  of  the 
thorax  are  not  symmetrical,  the  right  being  the  larger.  In 
the  female  the  general  capacity  is  less,  and  the  sternum  is 
shorter  than  in  the  male.  In  a  transverse  section  of  the  chest 
the  vertebrae  are  seen  to  project  far  forward  toward  the 
sternum,  the  shape  resembling  the  Greek  omega.  The  sternal 
notch  corresponds  with  the  disc  between  the  second  and  third 
dorsal  vertebrae,  and  at  this  point  there  is  a  space  of  only 
slightly  over  2  inches  between  the  sternum  and  vertebrae. 

The  chest  overlaps  the  neck  in  front  and  the  abdomen 
below.  In  the  neck  the  apex  of  the  lung  rises  about  |  inch 
above  the  clavicle,  while,  owing  to  the  dome-like  obliquity 
of  the  diaphragm,  which  is  attached  to  the  xiphoid  in  front, 
and  the  crurae  and  lumbar  vertebrae  behind,  there  is  a  region 
common  to  both  thorax  and  abdomen,  which  is  thoracic 
posteriorly,  and  abdominal  anteriorly. 

DEFORMITIES  of  the  chest  are  seen  in  association  with  various 
diseases.  Thus,  in  emphysema  it  is  described  as  being  barrel- 


THE  THORAX  151 

shaped.  In  pigeon-breast  the  sternum  and  cartilages  are 
prominent,  while  a  sulcus  exists  along  the  costo-chondral 
line,  due,  it  is  supposed,  to  yielding  of  this,  the  weakest  part, 
where  there  is  some  impediment  to  respiration.  Deformities 
of  the  spine  often  have  a  marked  effect  upon  the  thorax. 
In  Pott's  disease,  with  angular  curvature  of  the  spine,  the 
sternum  may  project  forwards,  increasing  the  antero-posterior 
diameter,  and  the  ribs  may  be  crowded  together,  so  as  even 
in  very  severe  cases  to  overlap  the  iliac  crests.  In  scoliosis,  or 
lateral  curvature  of  the  spine,  in  which  the  vertebrae  rotate 
so  that  their  bodies  point  to  the  convexity  of  the  curve,  the 
ribs,  being  firmly  attached  to  the  vertebrae  by  the  costo- 
vertebral  and  transverse  ligaments,  move  with  them,  rendering 
the  angles  very  prominent  and  the  front  of  the  chest  flattened 
on  the  convex  side,  while  on  the  concave  side  the  angles  are 
flat  and  the  front  of  the  chest  prominent.  Further,  on  the 
convex  side  the  ribs  are  wide  apart,  while  they  are  crowded 
together  on  the  concave. 

The  Sternum. — Behind  the  MANUBRIUM  there  is  little  or 
no  lung,  the  space  being  occupied  chiefly  by  the  vessels,  etc. 
The  left  innominate  vein  is  most  superficial,  and  lies  just 
below  the  upper  border  of  the  manubrium.  Then  come  the 
main  branches  of  the  aortic  arch,  then  the  trachea  bifurcating 
at  the  manubrio-gladiolar  junction,  and,  most  deeply,  the 
oesophagus.  The  highest  portion  of  the  aortic  arch  is  about 
i  inch  below  the  upper  border  of  the  manubrium,  and  the 
course  of  the  innominate  artery  is  indicated  by  a  line  from 
the  right  sterno-clavicular  articulation  to  the  middle  of  the 
manubrio-gladiolar  junction. 

The  junction  of  the  manubrium  and  gladiolus  sterni  is 
marked  by  a  transverse  ridge,  which  can  nearly  always  be 
felt,  and  which  indicates  the  level  of  the  cartilage  of  the  second 
rib,  the  bifurcation  of  the  trachea,  and  the  disc  between  the 
fourth  and  fifth  dorsal  vertebrae.  The  two  bones  generally 
lie  at  an  angle  to  one  another,  which  is  supposed  to  be  par- 
ticularly marked  in  pulmonary  affections,  and  which  is  referred 
to  as  the  ANGULUS  STERNALIS.  They  do  not  become  firmly 
united  until  middle  life,  and  dislocation  occasionally  occurs, 
the  gladiolus  and  ribs  being  displaced  forwards.  Fracture  of 
the  sternum  is  uncommon,  is  generally  transverse,  and  due  to 
violent  flexion  forwards  or  backwards.  It  also  occurs 


152  SURGICAL  ANATOMY 

generally  about  the  manubrio-gladiolar  junction,  and  owing 
to  the  thick  periosteal  covering  of  the  bone,  displacement  is 
generally  slight.  The  bone  has  occasionally  been  penetrated 
by  stabbing,  and  has  been  trephined  with  the  object  of  reaching 
the  mediastinum  and  pericardium,  a  similar  operation  having 
been  suggested  for  ligature  of  the  innominate. 

As  most  segments  of  the  gladiolus  are  developed  from  two 
lateral  centres  of  ossification,  want  of  union  between  these 
sometimes  occurs,  giving  rise  to  wide  median  fissures  of  the 
bone,  leaving  the  heart  uncovered  by  bone,  the  condition 
occasionally  being  associated  with  ectopia  cordis.  In  less 
severe  cases  an  aperture  may  be  met  with  in  the  gladiolus 
through  which  deep  suppurative  processes  may  pass  to  the 
surface,  or  superficial  infections  may  gain  access  to  deeper 
parts.  Deep  indentations  also  are  met  with  in  the  sternum, 
resulting  from  regular  pressure  applied  to  it  in  certain  trades, 
as  joiners  and  bootmakers. 

The  Ribs. — The  anterior  extremities  of  the  ribs  are  generally 
on  a  much  lower  level  than  their  posterior.  Thus,  the 
anterior  end  of  the  first  rib  is  on  a  level  with  the  head  of  the 
fourth,  the  second  with  the  sixth,  the  third  with  the  seventh, 
and  the  seventh  with  the  eleventh.  The  first  rib  is  the 
shortest,  the  seventh  the  longest,  and  the  ninth  the  most 
oblique.  In  counting  the  ribs  it  is  useful  to  remember  that 
the  manubrio-gladiolar  junction  denotes  the  position  of  the 
second  costal  cartilage.  The  male  nipple  is  generally  situated 
between  the  fourth  and  fifth  ribs.  When  the  arm  is  raised, 
the  first  visible  digitation  of  the  serratus  magnus  corresponds 
to  the  sixth  rib.  The  scapula  covers  the  second  to  the  seventh 
rib  inclusive,  and  when  the  arm  is  at  rest  and  applied  to  the 
side,  its  angle  reaches  the  level  of  the  eighth  rib.  The  twelfth 
rib  is  occasionally  -absent,  and,  on  the  other  hand,  accessory 
ribs  may  be  present.  These  generally  occur  in  the  lumbar 
or  cervical  region.  The  latter  are  generally  met  with  in  con- 
nection with  the  seventh  cervical  vertebrae,  and  sometimes 
give  rise  to  trouble  from  irritation  of  the  cords  of  the  brachial 
plexus,  necessitating  their  removal. 

The  ribs  are  very  elastic,  and  this  quality  is  increased  in 
young  persons  by  the  elastic  costal  cartilages,  and  hence  they 
frequently  escape  fracture,  even  when  the  violence  is  sufficient 
\o  damage  the  underlying  organs.  As  a  rule,  fractures  of 


THE  THORAX  153 

ribs  occur  in  older  persons.  Where  fracture  is  caused  by 
direct  Science,  the  pleura  is  apt  to  be  injured  by  driving  in 
of  the  fragments ;  whereas  in  fracture  from  indirect  violence, 
where  the  fracture  frequently  occurs  between  the  angle  and  the 
centre  of  the  bone,  the  fragments  tend  to  be  driven  out,  and 
the  pleura  generally  escapes.  In  addition  to  the  pleurae,  the 
lungs,  heart,  and  even  the  liver  and  spleen  may  be  damaged 
in  severe  cases  of  fracture.  The  ribs  most  frequently  frac- 
tured are  the  sixth,  seventh,  and  eighth,  while  the  first  is  very 
rarely  fractured,  and  the  second  and  third,  and  also  the  fourth, 
eleventh,  and  twelfth  generally  escape. 

As  a  rule,  the  fracture  is  not  attended  with  displacement, 
save  in  severe  injuries,  where  several  ribs  have  been  damaged, 
and  possibly  driven  in.  Ribs  have  been  occasionally  fractured 
by  muscular  violence,  as  in  sneezing  and  coughing,  but  prob- 
ably in  such  cases  have  been  affected  by  disease — as,  for 
example,  tubercle — which  very  frequently  affects  the  ribs 
(insane  rib),  giving  rise  to  superficial  cold  abscesses,  which, 
owing  to  the  laxriess  of  the  subcutaneous  tissues,  may  attain 
a  considerable  size. 

The  rickety  rosary  is  a  bilateral  enlargement  of  the  ribs  at 
the  costo-chondral  junction,  due  to  rickets. 

The  COSTAL  CARTILAGES  increase  in  length  up  to  the  seventh 
or  eighth,  and  then  again  decrease,  and  the  lower  cartilages 
run  obliquely  upwards  from  the  ribs  to  the  sternum.  The 
cartilages  are  occasionally  fractured  in  older  persons  by  direct 
violence,  producing  a  sharp  transverse  fracture,  which 
generally  heals  by  tissue  containing  osseous  matter. 

The  INTERCOSTAL  SPACES  are  wider  in  front  than  behind, 
and  increase  in  breadth  from  above  downwards.  The  widest 
space  is  the  third,  then  the  second  and  first.  They  are- 
increased  on  inspiration,  by  emphysema,  pleural  effusions,  etc. 
When  collapse  of  the  lung  has  occurred,  on  the  other  hand,  the 
ribs  become  flattened  and  crowded  together,  while  the 
diaphragm  ascends. 

Paracentesis  (tapping  of  the  chest),  or  thoracotomy 
(incision  into  the  chest  through  an  intercostal  space),  is 
generally  performed  in  the  sixth  or  seventh  space  and  in  the 
midaxillary  line,  the  instrument  being  entered  during  inspira- 
tion as  close  to  the  upper  border  of  the  lower  rib  as  possible, 
so  as  to  avoid  the  intercostal  vessels.  Tapping  should  not  be 


154  SURGICAL  ANATOMY 

performed  behind  the  angles  of  the  ribs,  owing  to  the  thick 
layer  of  muscles,  and  owing  to  the  oblique  course  of  the  inter- 
costal artery,  nor  should  it  be  performed  through  the  lower 
spaces,  owing  to  the  danger  of  wounding  the  diaphragm. 
When  done  in  the  eighth  or  ninth  space,  the  puncture  should 
be  made  just  in  front  of  the  line  of  the  angle  of  the  scapula. 
Where  more  space  is  required,  a  portion  of  one  or  more  ribs 
may  be  excised  subperiosteally,  so  as  to  avoid  damage  to  the 
vessels. 

The  intercostal  spaces  are  occupied  by  the  INTERCOSTAL 
MUSCLES,  which  consist  of  an  external  and  internal  layer. 
The  fibres  of  the  external  set,  like  those  of  the  external  oblique 
of  the  abdomen;  run  downwards  and  forwards,  and  extend 
from  the  tubercles  of  the  ribs  posteriorly  to  the  costo-chondral 
junctions  anteriorly,  beyond  which  a  membranous  layer 
extends  forwards  to  the  sternum.  The  fibres  of  the  internal 
layer,  like  those  of  the  internal  oblique,  run  at  right  angles  to 
those  of  the  external,  and  extend  from  the  sternum  to  the 
angles  of  the  ribs,  beyond  which  a  membranous  layer  extends 
backwards  to  the  vertebrae.  Pus  arising  from  disease  of  the 
vertebrae,  or  adjoining  portions  of  ribs,  may  be  conducted 
along  between  these  muscular  layers,  and  thus  present 
anteriorly.  A  thin  layer  of  connective  tissue  (the  endo- 
thoracic  fascia)  exists  between  the  ribs  and  intercostal  muscles 
and  the  parietal  pleura. 

The  INTERCOSTAL  ARTERIES  are  given  off  from  the  aorta, 
with  the  exception  of  the  first  two,  which  arise  from  the 
superior  intercostal  of  the  subclavian.  The  arteries  of  the 
right  side  cross  the  front  of  the  vertebral  column  behind  the 
oesophagus,  thoracic  duct,  and  vena  azygos  major.  Each 
runs  out  and  backwards  on  the  side  of  the  vertebral  body  to 
the  intercostal  space  behind  the  pleura  and  sympathetic  cord, 
and  then  ascends  to  the  lower  border  of  the  rib  forming  the 
upper  boundary  of  the  space,  whence  it  runs  forward  in  the 
subcostal  groove,  at  first  between  the  pleura  and  the  posterior 
intercostal  membrane,  and  then,  having  pierced  the  mem- 
brane, between  it  and  the  external  intercostal  muscle,  and, 
farther  out,  between  the  two  muscles.  In  the  groove  the 
artery  is  accompanied  by  the  vein,  which  lies  above  it,  and  the 
nerve,  which  lies  below  it.  At  the  anterior  end  of  the  space  it 
anastomoses  with  the  intercostal  branches  of  the  internal 


THE  THORAX  155 

mammary.  The  third,  fourth,  and  fifth  intercostal  arteries 
give  off  mammary  branches,  which  supply  the  breast,  and 
become  enlarged  during  lactation. 

The  INTERNAL  MAMMARY  ARTERY  arises  from  the  subclavian 
artery  at  the  inner  border  of  the  scalenus  anticus,  and  runs 
downwards,  inwards,  and  forwards,  the  phrenic  nerve  crossing 
it  in  front,  to  the  under  surface  of  the  first  costal  cartilage,  and 
then  runs  downwards  about  \  inch  beyond  the  border  of  the 
sternum,  in  front  of  the  pleura  and  triangularis  sterni  muscle. 
It  anastomoses  with  the  intercostal  arteries,  and  with  the 
artery  of  the  other  side,  and  sends  off  perforating  branches 
to  the  pectoralis  major  and  mammary  gland,  that  in  the  second 
space  being  generally  the  largest,  and  ends  in  the  musculo- 
phrenic  artery,  which  supplies  the  diaphragm,  and  the  superior 
epigastric,  which  anastomoses  with  the  deep  epigastric. 
These  anastomoses  are  of  importance,  as  they  come  into  play 
after  ligature  of  the  subclavian  or  axillary,  and  common  or 
external  iliac  vessels.  The  internal  mammary  is  most  easily 
ligatured  through  the  second  intercostal  space. 

The   anterior   mediastinal    LYMPHATIC    GLANDS,    generally 
two  in  number  for  each  intercostal  space,  lie  round  the  artery. 
They  receive  lymph  from  the  diaphragm,  anterior  portions  of 
the  intercostal  spaces,  and  inner  portion  of  the  mammary 
gland.     This  latter  communication  should  be  remembered  in 
cases  of  extensive  tubercular  or  carcinomatous  affections  of 
the  breast,  and  the  possibility  of  involvement  of  these  glands 
considered.     While    the    five    upper    INTERCOSTAL    NERVES 
supply  the  chest-wall  and  integument  (the  intercosto-humeral 
of  the  second  supplying  the  skin  on  the  inner  and  posterior 
aspects  of  the  upper  two-thirds  of  the  arm),  the  lower  six 
extend  to  the  abdomen,  supplying  skin,  muscles,  and  parietal 
peritoneum.     Painful  ajjections  of  these  latter  nerves,  there- 
fore, frequently  give  rise  to  abdominal  tenderness  and  rigidity, 
which  may  be  mistakenly  regarded  as  arising  from  peritonitis, 
and  somewhat  similar  symptoms  are  not  infrequently  mani- 
fested in  the  early  stages  of  spinal  caries,  the  patient  referring 
the  pain  to  the  region  of  the  umbilicus.     A  painful  affection  of 
the  upper  intercostal  nerves  is  termed  '  intercostal  neuralgia,' 
and  may  be  followed  by  herpes  along  the  course  of  the  nerve 
(herpes  zoster,  or  shingles).     The  triangularis  sterni  muscle 
rises  from  the  deep  surface  of  the  lower  portion  of  the  sternum , 


156  SURGICAL  ANATOMY 

xiphoid,  and  fifth,  sixth,  and  seventh  costal  cartilages,  and  is 
inserted  into  the  deep  surfaces  of  the  second  to  fifth  costal 
cartilages. 

The  MAMMARY  GLAND  is  of  epiblastic  origin,  and  retains 
its  rudimentary  condition  of  a  number  of  branching  ducts 
with  little  glandular  tissue  until  puberty,  when  the  gland 
tissue  rapidly  increases.  A  further  marked  increase  of  gland 
at  the  expense  of  fibrous  tissue  takes  place  during  pregnancy. 
Between  pregnancies,  and  after  the  menopause,  the  gland 
tissue  decreases  in  bulk,  .fatty  tissue  taking  its  place.  In  the 
male  the  gland  maintains  a  rudimentary  condition,  as  a  rule. 
The  gland  consists  of  some  FIFTEEN  LOBULES,  which  are  sur- 
rounded and  separated  from  one  another  by  vascular  septa 
of  fibrous  tissue,  which  bind  them  together,  forming  a  capsule, 
and  also  form  many  fine  connections  with  the  deeper  portions 
of  the  skin  (suspensory  ligament;  of  Cooper),  with  the  peri- 
glandular  connective  tissue,  and  a  very  loose  connection  with 
the  subjacent  pectoral  fascia.  A  bursa  occasionally  exists 
between  the  gland  and  the  pectoral  fascia,  and  in  the  loose 
connective  tissue  a  submammary  abscess  sometimes  develops. 
The  main  portion  of  the  gland  is  pyramidal,  its  base  lying  on 
the  fascia  of  the  pectoralis  major  from  the  second  to  the  sixth 
rib.  A  considerable  portion  of  the  gland  overlaps  the 
pectoralis  major  externally,  and  rests  on  the  serratus  magnus 
within  the  axilla,  extending  upwards  frequently  to  the  upper 
border  of  the  third  rib,  while  internally  and  below  it  overlaps 
the  rectus  abdominis  and  external  oblique.  Isolated  portions 
of  the  gland  tissue  may  be  found  penetrating  or  even  under 
the  pectoral  fascia  in  contact  with  the  fibres  of  the  pectoralis 
muscle.  The  NIPPLE  is  normally  situated  in  the  fourth  inter- 
costal space,  |  inch  from  the  costo-chondral  junction,  at  the 
summit  of  the  breast ;  but  as  the  chest-wall  rises  more  than 
the  breast  on  inspiration,  the  nipple  is  then  opposite  the  fifth 
space.  In  nulliparae  it  frequently  projects  but  slightly,  but 
may  be  elongated  in  multipart,  projecting  forwards  and 
outwards.  It  contains  erectile  and  unstriped  muscular  tissue, 
and  is  covered  by  thin  skin,  on  which  the  orifices  of  the 
fifteen  milk,  or  lactiferous,  ducts  present.  Within  the  ni pplc 
each  duct  presents  an  ampulla,  or  dilatation,  and  on  leaving 
the  nipple  the  ducts  radiate  outward  to  the  various  lobes. 
Hence  in  incising  a  breast  it  is  important  to  make  the  incision 


THE  THORAX  157 

radiate  from  the  nipple,  so  as  to  avoid  division  of  these  ducts. 
The  AR£OLA  is  circular  in  outline,  measures  from  i  to  i  J  inches 
in  diameter,  and  is  covered  by  thin  skin,  which  may  be  pink 
in  colour  or  pigmented,  and  becomes  darker  during  pregnancy. 
A  number  of  subcutaneous  sebaceous  glands  (of  Montgomery) 
frequently  give  a  fine  nodular  appearance  to  the  areola. 

The  SKIN  of  the  breast  is  normally  thin,  smooth,  and  freely 
movable,  the  subjacent  veins  being  frequently  visible  through 
it,  especially  during  lactation.  The  BLOOD-SUPPLY  of  the 
breast  is  from  (i)  the  external  mammary  branches  of  the  long 
thoracic  of  the  axillary  ;  (2)  anterior  perforating  branches  of 
the  internal  mammary  through  the  second,  third,  and  fourth 
spaces  ;  and  (3)  the  lateral  branches  of  the  second,  third,  and 
fourth  intercostal  arteries.  The  veins  join  the  internal 
mammary  and  axillary,  while  some  small  ones  join  tributaries 
of  the  external  jugular. 

The  lymphatic  supply  of  the  breast  is  of  the  greatest  impor- 
tance surgically,  as  it  is  along  this  system  that  carcinoma 
spreads  from  the  breast  to  invade  the  general  system.  Fine 
lymphatics  surround  the  acini  and  ducts,  and  communicate 
with  larger  channels  in  the  interlobular  connective  tissue, 
which  in  turn  communicate  with  those  in  the  subcutaneous 
tissues  (by  running  along  the  suspensory  ligaments),  and 
submammary  tissues,  and  those  which  penetrate  the  pectoral 
fascia.  The  efferent  vessels  pass  from  the  margin  of  the  gland 
to  the  pectoral  group  of  the  axillary  lymphatics  situated  along 
the  anterior  border  of  the  axilla,  and  the  central  superficial 
group,  and  thence  to  the  deep  glands  grouped  round  the 
axillary  vein,  some  lymphatics  passing  to  this  deep  group 
direct.  A  few  lymphatics  lead  to  the  infraclavicular  glands, 
which  lie  around  the  termination  of  the  cephalic  vein  between 
the  pectoralis  major  and  deltoid,  and  from  thence  beneath 
the  clavicle  to  the  lower  deep  cervical  glands,  which  are  grouped 
round  the  lower  portion  of  the  internal  jugular  vein. 
Lymphatics  from  the  deep  axillary  group  probably  also  reach 
this  deep  cervical  group,  and  from  thence  the  lymph  on  the 
right  side  is  poured  into  the  right  lymphatic  duct,  and  on  the 
left  into  the  thoracic  duct.  Lymphatics  also  pass  from  the 
inner  side  of  the  breast  to  the  anterior  mediastinal  glands  in 
the  first  four  intercostal  spaces,  which  are  grouped  round  the 
internal  mammary  artery.  Thus  it  will  be  seen  that,  in  a 


I58 


SURGICAL  ANATOMY 


FIG.  17.— DIAGRAM  OF  BREAST  LYMPHATICS. 


1.  Pect.  major. 

2.  Pect.  minor. 

3.  Breast  dissected,  showing 

acini,  ducts,  and  am- 
pullae. 

4.  Areola  and  nipple,  showing 

openings  of  ducts. 

5.  Inferior  thoracic  group  sur- 

rounding external  mam- 
mary artery  (long  thor- 
acic). 


(Much  modified  from  Testut.) 

6  and  7.     Subscapular   group  16. 

surrounding  subscapular  17. 

artery.         ,  18. 

8.  Deep  brachial  group. 

9.  Nerve  of  Wrisberg.  19. 
10.  Axillary  vein.  20. 
n.  Ulnar  nerve.  21. 

12.  Axillary  artery.  22. 

13.  Cephalic  vein.  23. 

14.  Pect.  major  tendon.  24. 

15.  Coraco-brachial  and  biceps. 


Pect.  minor  tendon. 
Brachial  plexus. 
Supraclavicular  group  (deep 

cervical). 

Infraclavicular  group. 
Anterior  mediastinal  group. 
Pectoral  group. 
Central  superficial  group. 
Deep  group. 
Serratus  magnus. 


THE  THORAX  159 

case  of,  carcinoma  of  the  breast,  we  may  have  lymphatic 
affection  in  the  axilla,  under  the  clavicle,  above  the  clavicle, 
and  thence  to  the  lymphatic  duct,  whence  the  infection  would 
become  general.  The  mass  in  the  axilla  causes  oedema 
of  the  arm  from  .pressure  on  the  vessels  and  lymphatics, 
and  pain  over  the  back  of  the  arm  above  the  elbow  from 
pressure  on  the  intercosto-humeral  nerve  which  traverses  the 
central  axillary  glands ;  while  the  brachial  plexus  may  also 
become  involved,  and  spreading  to  the  anterior  medias- 
tinum may  occur.  The  lymphatics  traversing  the  pectoral 
fascia  become  involved,  the  gland  then  becoming  fixed  to  the 
underlying  structures,  and  so  rendered  immovable.  The 
carcinoma  may  also  spread  by  the  lymphatics  in  the  suspensory 
ligaments  (which  become  contracted,  causing  sometimes  an 
orange-skin  appearance  of  the  overlying  skin,  or  at  others  a 
general  flattening),  and  those  surrounding  the  ducts  (producing 
retraction  of  the  nipple) .  The  subcutaneous  lymphatic  system  is 
most  prone  to  infection  after  ulceration  of  the  skin  has 
occurred,  and  once  it  is  affected  dissemination  is  very  rapid, 
nodules  being  scattered  over  the  skin  of  the  chest  and  trunk 
generally,  producing,  if  the  carcinoma  be  of  the  scirrhus  type, 
the  condition  known  as  cancer  en  cuirasse,  in  which  great  con- 
traction of  the  whole  skin  occurs,  crushing  the  chest  and 
killing  by  suffocation. 

Carcinoma  is  the  most  common  tumour  of  the  breast,  and 
it  occurs  in  many  different  forms — scirrhus,  in  which  there  is 
abundant  fibrous  tissue  ;  adeno- carcinoma,  which  is  glandular 
in  microscopic  section,  and  clinically  presents-one  or  more 
bosses  on  the  br*east,  covered  by  shiny,  discoloured  skin  ;  acute 
carcinoma,  which  rapidly  involves  the  whole  breast,  and  is 
not  unlike  an  abscess  clinically,  while  microscopically  it 
presents  masses  of  loosely-packed  cells  with  but  little  stroma  ; 
Paget's  nipple,  which  begins  as  an  eczema  of  the  nipple  and 
areola,  and  gradually  spreads  throughout  the  ducts. 

Sarcoma,  frequently  of  the  adenomatous  type,  sometimes 
occurs  in  the  breast,  and,  as  it  is  generally  encapsulated  in 
the  early  stages,  is  of  slow  growth. 

Of  the  simple  tumours,  vario'us  forms  of  adenoma  are  most 
common,  and  where  situated  in  the  lower  segment,  and  deeply 
in  the  breast  substance,  are  best  removed  through  a  curved 
incision  along  the  lower  border  of  the  breast,  the  gland  being 


160  SURGICAL  ANATOMY 

lifted  up,  and  the  tumour  extracted  from  its  under  surface 
(Thomas).  Cysts  also  occur,  either  simple  retention  cysts, 
due  to  blocking  of  the  milk  ducts  (galactocele),  or  papillo- 
matous  cysts. 

Inflammation  of  the  breast  (mastitis)  may  be  followed  by 
abscess,  which  is  generally  INTRAMAMMARY,  but  may  be  supra- 
or  inframammary,  the  latter  being  not  infrequently  due  to 
tubercle,  and  sometimes  occurring  in  the  bursa  beneath  the 
breast.  The  typical  pyogenic  abscess  is  intramammary. 

The  breasts  are  frequently  unsymmetrical,  the  left  being 
generally  the  larger.  Absence  of  one  or  both  breasts  (amazia) 
is  very  rare,  but  the  presence  of  supernumerary  nipples 
(polythelia)  and  glands  (polymazia)  is  more  common.  The 
additional  glands  generally  lie  below  and  inside  the  normal, 
but  may  occur  at  any  point  along  a  line  extending  from  the 
axilla  to  the  groin.  They  have  also  been  found  on  the  thigh, 
back,  buttock,  etc. 

In  palpating  the  breast  it  is  important  to  remember  that, 
if  the  breast  be  taken  between  the  finger  and  thumb,  the  normal 
breast  tissue  will  give  a  sensation  not  unlike  that  of  a  tumour. 
The  correct  method,  therefore,  is  to  lay  the  palm  of  the  hand 
and  fingers  flat  on  the  breast,  allowing  the  nipple  to  project 
between  the  fingers,  and  then  to  palpate  the  gland  against  the 
chest-wall. 

The  nerve-supply  of  the  breast  is  from  the  fourth,  fifth,  and 
sixth  intercostals,  by  which  filaments  of  the  dorsal  sympa- 
thetic also  reach  it. 

The  THORACIC  CAVITY  contains  the  lungs,  which  are 
separated  by  the  mediastinum,  containing  the  heart,  vessels, 
trachea,  etc.  The  mediastinum  extends  from  the  sternum  to 
the  spine,  forming  a  complete  septum  between  the  lungs,  and 
is  deflected  somewhat  toward  the  left.  It  is  bounded  by  the 
diaphragm  below,  but  is  open  above,  while  laterally  it  is 
bounded  by  the  pleurae.  Its  upper  part  contains  the  aortic 
arch  and  great  vessels,  innominate  veins,  and  upper  portion 
of  the  superior  vena  cava  ;  trachea,  oesophagus  and  thoracic 
duct ;  phrenic,  pneumogastric,  left  recurrent  laryngeal  and 
cardiac  nerves  ;  and  thymus  gland.  The  lower  part  is  chiefly 
occupied  by  the  heart  and  pericardium  and  phrenic  nerves 
placed  centrally.  In  front  of  the  pericardium  and  behind  the 
gladiolus  the  mediastinum  is  practically  non-existent  in  its 


THE  THORAX  161 

upper  segment,  owing  to  the  pleurae  coming  in  contact,  but 
below  the  fourth  costal  cartilage  the  pleurae  diverge.  This 
anterior  portion  contains  areolar  tissue  and  lymphatic  glands 
and  vessels.  Behind  the  pericardium  the  lower  mediastinum 
communicates  with  the  upper,  and  contains  the  descending 
thoracic  aorta,  azygos  veins,  oesophagus,  thoracic  duct,  and 
two  pneumogastric  nerves.  The  azygos  veins  commence  below 
in  the  lumbar  veins,  and  communicate  with  the  iliacs,  renals, 
etc. ;  receive  blood  from  the  intercostal  veins ;  and  discharge 
into  the  superior  vena  cava.  They  may  be  of  great  assistance 
where  the  main  trunk  is  obliterated,  and  when  themselves 
pressed  on  tend  to  cause  oedema  of  the  chest-wall  from  engorge- 
ment of  the  intercostal  veins.  The  mediastinum  is  sometimes 
the  seat  of  abscesses  which  may  develop  from  the  contained 
glands  or  the  dorsal  vertebrae,  or  may  extend  to  it  from  the 
neck.  Such  abscesses  are  generally  chronic,  and  become  of 
large  size,  pressing  upon  the  trachea,  bronchi,  or  oesophagus. 
Sarcomatous  tumours  and  aortic  aneurism  also  give  rise  to 
pressure  symptoms,  the  effects  on  the  veins  being  often  par- 
ticularly obvious,  the  face,  neck,  and  upper  limbs  becoming 
cedematous  from  pressure  on  the  superior  vena  cava,  and 
innominate,  while  the  veins  of  the  trunk  also  become  distended 
from  the  increased  flow  of  blood  through  them.  The  vagus, 
recurrent  laryngeal,  and  sympathetic  nerves  also  become 
affected. 

The  FIBROUS  PERICARDIUM,  of  inverted  conical  shape,  is 
attached  above  to  the  roots  of  the  great  vessels,  and  below  to 
the  central  tendon  of  the  diaphragm.  Laterally  and  anteriorly 
it  is  bounded  by  the  pleurae,  while  posteriorly  it  is  largely  free. 
Above,  the  fibrous  pericardium  is  lost  upon  the  great  vessels 
about  the  level  of  the  centre  of  the  manubrium,  whence,  how- 
ever, it  becomes  connected  with  the  pretracheal  layer  of  the 
deep  cervical  fascia  (cervico-pericardiac  fascia).  This  con- 
nection between  larynx,  pericardium,  and  diaphragm  explains 
why  the  larynx  descends  slightly  on  inspiration.  Below, 
owing  to  the  base  sloping  downwards  and  forwards  to  the 
left,  it  has  indirect  relationships  to  the  left  lobe  of  the  liver 
and  upper  wall  of  the  stomach.  This  latter  relationship  helps 
to  explain  the  cases  of  fainting  which  sometimes  occur  from 
flatulent  distension  of  the  stomach  pressing  directly  upon  the 
heart.  The  lower  extremity  of  the  thymus  gland  rests  upon 

ii 


162 


SURGICAL  ANATOMY 


the  upper  portion  of  the  anterior  surface,  and  a  small  portion 
of  this  anterior  surface  to  the  left  of  the  middle  line,  and  behind 
the  sternum  and  fourth,  fifth,  and  sixth  ribs,  comes  into 
relationship  with  the  chest-wall.  The  posterior  surface  is 


FIG.  18. — TRANSVERSE  SECTION  OF  THE  THORAX  THROUGH  THE  SECOND 
STERNEBRA  IN  FRONT  AND  THE  BODY  OF  THE  NINTH  THORACIC 
VERTEBRA  BEHIND,  SHOWING  THE  REFLECTIONS  OF  THE  PLEURA 

AND    THE    POSITION    OF   THE    VlSCERA. 


S.   Sternum. 

A.M.   Anterior  mediastinum. 
A.  A.  Ascending  aorta. 
P.  A.  Pulmonary  artery. 
R.A.A.   Right  auricular  appendix. 
R.A.  Right  auricle. 
M.M.  Middle  mediastinum. 
L.A.  Left  auricle. 


(From  Buchanan's  "  Anatomy.") 

P.M.   Posterior  mediastinum. 

O.  (Esophagus. 

I). A.   Descending  thoracic  aorta. 
T.V.  Thoracic  vertebra. 

M.   Middle  lobe  of  right  lung. 
R.U.   Right  upper  lobe. 
R.L.  Right  lower  lobe. 
L.  U.  Left  upper  lobe. 
L.L.   Left  lower  lobe. 


1.  Internal  mammary  vessels. 

2.  Right  chief  pulmonary  fissure. 

3.  Right  vagus  nerve. 

4.  Right  azygos  vein. 

5.  Thoracic  duct. 


6.  Left  vagus  nerve. 

7.  Left  pulmonary  fissure. 

8.  Pulmonary  pleura. 

9.  Pleural  interval. 
10.   Parietal  pleura. 


related  to  the  thoracic  aorta  and  duct,  the  oesophagus  and 
vagi  nerves,  and  the  bifurcation  of  the  trachea.  Within  the 
fibrous  pericardium  is  the  SEROUS  PERICARDIUM,  which,  like 
the  peritoneum,  is  a  closed  sac  containing  a  little  fluid,  the 
parietal  layer  of  which  invests  the  inner  surface  of  the  fibrous 


THE  THORAX  163 

layer,  while  the  visceral  partially  ensheaths  the  heart  and 
great  vessels.  The  aorta  and  pulmonary  artery  are  enclosed 
together  in  a  complete  sheath  of  visceral  layer,  which  is 
separated  from  the  auricles,  which  lie  in  front,  by  a  passage, 
called  the  great  transverse  sinus,  running  from  right  to  left. 
The  other  vessels  receive  partial  coverings,  and  also  present 
sinuses  separating  them  from  the  serous  pericardium.  The 
pericardium  may  be  occupied  by  a  considerable  amount  of 
fluid  without  pressing  unduly  upon  the  heart,  the  sac  stretch- 
ing, if  time  be  given  it,  at  the  expense  of  the  lungs,  the  above- 
mentioned  sinuses,  etc.  In  such  cases  the  pericardium  has 
been  known  to  contain  fully  2  pints  of  fluid,  the  superficial 
area  of  heart  dulness  being  increased,  and  the  heart,  which 
has  its  root  in  the  great  vessels,  being  pushed  upwards  and 
backwards,  its  impulse  becoming  imperceptible,  and  the 
diaphragm  being  depressed.  In  examining  such  conditions 
it  is  important  to  know  the  normal  relationship  of  the  anterior 
surface  of  the  heart  to  the  chest- wall.  The  projection  of  the 
anterior  surface,  then,  may  be  defined  by  four  lines — above, 
across  the  sternum  just  above  the  upper  borders  of  the  third 
costal  cartilages,  and  extending  beyond  it  for  J  inch  on  the 
right  and  i  inch  on  the  left ;  below,  from  a  point  on  the  right 
sixth  costal  cartilage,  f  inch  from  the  sternal  margin,  down- 
wards to  the  left  fifth  intercostal  space,  3^  inches  from  mid- 
sternum  (this  latter  point  represents  the  position  of  the  apex)  ; 
on  the  right,  from  the  extremities  of  the  top  and  bottom  lines, 
in  a  curve  with  the  convexity  outwards,  which  reaches  at  the 
level  of  the  fourth  costal  cartilage,  a  point  i \  inches  from  the 
mid-sternal  line  ;  on  the  left,  also  curved  with  the  convexity 
outwards,  and  joining  the  extremities  of  the  top  and  bottom 
lines.  A  small  triangular  portion  of  the  heart,  chiefly  right 
ventricle,  is  left  uncovered  by  lung,  and  is  defined  by  drawing 
a  vertical  line  along  the  mid-sternum  from  the  lower  border 
of  the  fourth  costal  cartilage  to  the  junction  of  the  gladiolus 
and  xiphoid,  and  joining  either  extremity  of  this  with  the 
apex  in  the  fifth  intercostal  space.  Where  effusions  come  on 
rapidly,  serious  consequences  may  follow  even  comparatively 
slight  accumulations,  and  in  such  cases  it  may  be  necessary 
to  tap  the  pericardium,  or,  where  the  fluid  is  purulent,  to  drain 
it.  Tapping  is  best  done  through  the  sixth  left  intercostal 
space,  keeping  close  to  the  sternum,  so  as  to  avoid  the  internal 

II — 2 


1 64  SURGICAL  ANATOMY 

mammary  artery.  The  space  is  narrow,  and  the  needle  should 
not  be  introduced  much  more  than  an  inch,  lest  the  heart  be 
wounded.  Where  it  is  necessary  to  open  up  the  pericardium 
(pericardotomy)  for  draining  or  stitching  cardiac  wounds,  a 
vertical  incision  along  the  left  margin  of  the  sternum,  from  the 
fourth  to  seventh  costal  cartilage,  is  made,  and  the  sternum 
and  cartilages  exposed.  The  fifth  cartilage  is  first  cut  close  to 
the  sternum,  and  then  raised,  the  underlying  tissues  being 
carefully  reflected  from  it,  so  as  to  avoid  the  internal  mammary 
artery,  and  a  piece  cut  out.  The  sixth  cartilage  is  similarly 
treated.  Then  the  triangularis  sterni  muscle  is  incised  verti- 
cally, close  to  the  sternal  margin,  the  soft  tissues  carefully 
reflected,  the  pericardium  exposed,  picked  up,  and  incised, 
also  vertically,  for  about  an  inch,  the  pericardial  edges  being 
afterwards  sutured  to  the  subcutaneous  tissues  to  prevent 
dissemination  of  purulent  material.  It  should  be  remem- 
bered, however,  in  connection  with  operations  on  the  pericar- 
dium, that  the  area  left  uncovered  by  the  pleura  varies,  the 
left  pleura  occasionally  overlapping  practically  the  entire 
pericardium. 

The  HEART  is  somewhat  pyramidal  in  shape,  its  long  axis 
being  nearly  horizontal,  and  directed  downwards,  forwards, 
and  to  the  left.  The  anterior  surface  presents  itself  when  the 
pericardium  is  opened  from  the  front,  and  consists  of  the  right 
auricle,  and  occupying  most  of  the  surface,  the  right  ventricle  ; 
the  tip  of  the  left  auricular  appendix,  and  a  comparatively 
small  portion  of  the  left  ventricle,  separated  from  the  right 
ventricle  by  the  anterior  interventricular  furrow  (which  lodges 
a  branch  of  the  left  coronary  artery,  and  the  great  cardiac 
vein,  surrounded  by  fatty  tissue).  The  other  structures 
exposed  from  the  front  are  (a)  the  pulmonary  artery,  whose 
valve  is  situated  behind  the  upper  edge  of  the  third  left  costal 
cartilage  close  to  the  sternum  ;  (b)  the  ascending  aorta,  whose 
valve  is  behind  the  left  border  of  the  sternum  close  to  the 
lower  edge  of  the  third  cartilage.  The  trunk  ascends  behind 
the  second  right  cartilage,  and  arches  over  the  pulmonary 
arteries,  the  convexity  of  the  arch  corresponding  to  the 
junction  of  the  manubrium  and  gladiolus.  It  gives  off  the 
innominate  and  left  carotid  arteries  opposite  the  centre  of  the 
manubrium,  which  vessels  run  up  to  either  sterno-clavicular 
joint ;  (c)  to  the  right  of  the  aorta,  a  small  portion  of  the 


THE  THORAX  165 

superior yen a  cava.  The  tricuspid  valve  lies  behind  the  middle 
of  the  sternum,  about  the  level  of  the  fourth  costal  cartilage, 
and  the  mitral  behind  the  third  intercostal  space,  i  inch  to  the 
left  of  the  sternum.  All  the  valves,  therefore,  are  so  situated 
that  the  mouth  of  an  ordinary  stethoscope  placed  over  the 
left  margin  of  the  sternum  at  the  third  intercostal  space  will 
cover  a  portion  of  each.  It  will  be  remembered  that  the 
orifices  of  the  venae  cavae  are  practically  valveless.  The 
superior  vena  cava  begins  opposite  the  lower  border  of  the  first 
right  cartilage,  by  the  union  of  the  two  innominate  veins,  and 
descends,  curving  slightly  to  the  left,  to  the  third  right  costal 
cartilage,  where  it  enters  the  right  auricle.  These  relation- 
ships are  of  importance  with  reference  to  wounds  of  the  chest. 
Where  the  heart  is  involved,  the  right  ventricle  most  frequently 
suffers,  then  the  left  ventricle,  and  then  the  right  auricle. 
Wounds  of  the  ventricles  tend  to  be  less  serious  than  those 
of  the  auricles,  owing  to  the  thicker  and  more  muscular  coat, 
and  such  wounds  have  been  successfully  sutured.  In  some 
cases  death  from  cardiac  wounds  is  possibly  due  to  nervous 
shock  rather  than  to  bleeding. 

The  posterior  surface  of  the  heart  presents  the  auricles, 
particularly  the  left,  and  the  orifices  of  the  four  pulmonary 
veins  and  of  the  venae  cavae.  It  extends  from  the  fifth  to  the 
eighth  dorsal  spine.  The  lower  surface  presents  chiefly  the  left 
ventricle,  and  small  portions  of  the  right  ventricle  and  auricle. 
In  front,  near  the  apex,  the  heart  is  in  relation  with  the 
upper  wall  of  the  stomach,  the  diaphragm  and  pericardium 
intervening,  while  behind  it  lies  over  the  left  lobe  of  the  liver. 
Congenital  displacements  of  the  heart  are  occasionally  met  with- 
in some  cases  of  transposition  of  the  viscera  the  heart  may  be 
displaced  to  the  right  (dextrocardia) ,  or,  associated  with  con- 
genital sternal  fissure,  an  ectopia  cordis  may  occur,  the  heart 
projecting  forwards  through  the  aperture.  Pathologically,  the 
heart  is  most  frequently  displaced  laterally  by  pleural  affections, 
such  as  effusion  or  pneumothorax  ;  cirrhosis  of  the  lung,  by 
shrinking,  tends  to  drag  it  toward  the  affected  side,  while 
emphysema  depresses  the  diaphragm,  and  with  it  the  heart. 
The  heart  may  also  be  displaced  upwards  by  gaseous  dis- 
tension of  the  stomach,  ascites,  etc.  Changes  of  the  heart 
itself,  such  as  dilatation  and  hypertrophy,  also  affect  the 
position,  and  it  should  be  remembered  that  the  position  of 


1 66  SURGICAL  ANATOMY 

the  normal  heart  is  influenced  by  respiration  and  position  of 
the  body. 

The  THORACIC  AORTA  consists  of  three  parts — ascending, 
arch,  and  descending.  The  ascending  portion,  about  2  inches 
long,  runs  upwards,  forwards,  and  to  the  right  to  the  level 
of  the  upper  border  of  the  second  right  costal  cartilage.  It 
lies  within  the  pericardium,  and  is  invested,  along  with  the 
pulmonary  artery  behind  which  it  lies  at  its  origin,  by  the 
serous  layer.  At  its  commencement  it  presents  three  hemi- 
spherical projections,  the  aortic  sinuses  of  Valsalva,  and  also 
a  prominence  of  the  right  lateral  wall,  called  the  great  aortic 
sinus.  In  front  are  the  pulmonary  artery,  right  auricular 
appendix,  pericardium,  right  pleura  and  lung,  mediastinal 
tissue  and  sternum  ;  behind,  the  right  branch  of  the  pulmonary 
artery  and  right  bronchus  ;  on  the  right,  the  superior  vena 
cava  and  part  of  the  right  auricle  ;  on  the  left,  the  pulmonary 
artery. 

The  arch  of  the  aorta  commences  opposite  the  upper  border 
of  the  second  right  costal  cartilage,  and  ends  opposite  the 
lower  border  of  the  fourth  dorsal  vertebra.  The  highest  point 
is  opposite  the  centre  of  the  manubrium  and  third  dorsal  spine. 
The  concavity  of  the  arch  is  directed  downwards,  and  also 
backwards  and  to  the  right.  A  constriction  between  the 
origin  of  the  left  subclavian  and  the  obliterated  ductus 
arteriosus  is  called  the  isthmus,  and  the  expanding  portion 
beyond  the  spindle.  In  front  and  to  the  left  are  the  left 
mediastinal  pleura,  phrenic  nerve,  inferior  cardiac  branch  of 
vagus,  superior  cardiac  branch  of  sympathetic,  vagus  trunk, 
and  superior  intercostal  vein,  remains  of  thymus,  lung,  and 
pleura,  mediastinal  tissue,  and  manubrium.  Behind  and  to 
the  right  are  trachea,  oesophagus,  thoracic  duct,  and  left 
recurrent  laryngeal  nerve  ;  above  are  the  innominate  and  left 
common  carotid  and  subclavian  arteries,  and  left  innominate 
vein  ;  below  are  the  bifurcation  of  the  pulmonary  artery, 
obliterated  ductus  arteriosus,  left  recurrent  laryngeal  nerve, 
and  root  of  the  left  lung. 

The  descending  portion,  commencing  at  the  lower  border  of 
the  fourth  dorsal  vertebra,  lies  in  close  relationship  to  the  left 
side  of  the  column,  but  inclines  to  the  middle  line  as  it 
approaches  the  aortic  opening  in  the  diaphragm.  In  front 
are  the  root  of  the  left  lung,  (esophagus,  base  of  heart,  and 


THE  THORAX  167 

pericardium  ;  on  the  right,  oesophagus,  vena  azygos  major, 
thoracic  duct  and  pleura  ;  on  the  left,  pleura  and  lung  ;  and 
behind,  vertebral  column. 

The  thoracic  aorta  is  a  frequent  seat  of  ANEURISM.  When 
the  ascending  portion  is  affected,  the  tumour  ultimately 
projects  on  the  right  margin  of  the  sternum,  at  the  level  of  the 
second  and  third  costal  cartilages,  all  of  which  structures  may 
become  eroded,  while  the  clavicle  may  be  displaced  forwards. 
Owing  to  pressure  upon  the  superior  vena  cava,  there  is 
engorgement  of  the  veins  of  the  head,  neck,  and  upper  limbs. 
This  form  may  rupture  into  the  pericardium,  and  cause  death 
by  pressure  on  the  heart. 

Where  the  arch  is  affected,  the  tumour  presents  at  the  root 
of  the  neck  and  supr asternal  notch.  Pressure  on  the  veins 
produces  engorgement  ;  on  the  left  recurrent  laryngeal  nerve, 
spasm  of  the  cords  with  high-pitched  voice,  and  dyspnoea,  and, 
later,  aphonia  from  crushing  of  the  nerve.  Pressure  on  the 
trachea  produces  harsh  breathing,  dyspnoea,  and  cough  ;  on  the 
left  bronchus,  dyspnoea  ;  on  the  oesophagus,  dysphagia  ;  and 
on  the  phrenic  nerve,  hiccough,  and,  later,  paralysis  of  the 
left  side  of  the  diaphragm.  Tracheal  tugging,  detected  on 
slightly  raising  the  cricoid  cartilage  with  the  finger  and  thumb, 
is  due  to  the  expansile  pulsation  affecting  the  trachea.  Owing 
to  irritation  of  the  cervical  sympathetic,  which  conveys  fibres 
to  the  eye  from  the  lower  cervical  and  upper  dorsal  regions  of 
the  cord  (through  the  rami  communicantes,  to  the  carotid 
plexus,  and  so  to  the  ciliary  ganglion  within  the  orbit),  there 
is  dilatation  of  the  pupil  on  the  affected  side,  while,  should 
the  sympathetic  fibres  be  destroyed  by  increased  pressure  or 
stretching,  the  puprl  contracts  from  unopposed  action  of  the 
third  nerve.  Where  the  descending  aorta  is  affected,  the 
bodies  of  the  vertebrae  are  frequently  eroded,  while  the  inter- 
vertebral  discs  are  comparatively  resistant.  There  is  intense 
gnawing  pain  in  the  back,  referred  to  the  areas  supplied  by  the 
intercostal  nerves  involved,  and  herpes  zoster  may  develop. 

In  all  cases  where  there  is  external  swelling,  pulsation  of  an 
expansile  character  is  a  feature  which  serves  to  distinguish 
aneurism  from  most  tumours  or  abscesses.  In  addition  to 
presenting  the  symptoms  mentioned,  the  deep  forms  may  be 
diagnosed  by  X  rays.  Treatment  by  needling,  with  the  object 
of  slightly  injuring  the  sac  wall  and  producing  the  formation 


168  SURGICAL  ANATOMY 

of  a  white  thrombus  with  subsequent  formation  of  firm  fibrous 
tissue,  is  hopeful  if  the  case  be  got  early  (Mace wen). 

The  THORACIC  TRACHEA  lies  in  the  posterior  portion  of 
the  superior  mediastinum,  separated  from  the  vertebrae  by 
the  oesophagus.  In  front  it  is  related  to  the  aortic  arch  at  the 
level  of  the  fourth  dorsal  vertebra,  the  great  vessels,  left 
innominate  vein,  and  remains  of  the  thymus.  Immediately 
above  the  bifurcation  the  deep  cardiac  nerve  plexus  lies  in 
front  and  laterally.  On  the  right  side  it  is  in  relation  to  the 
vagus  and  pleura,  and  on  the  left  to  the  subclavian  artery  and 
recurrent  laryngeal  nerve.  The  bifurcation  of  the  trachea  lies 
opposite  the  interval  between  the  third  and  fourth  dorsal 
spines,  about  the  level  of  the  sternal  angle  in  front.  The  two 
bronchi  proceed  down  and  outwards  towards  the  hilus  of  the 
corresponding  lung,  the  left  bronchus  generally  being  twice 
as  long  as  the  right,  which  is  the  wider.  The  vena  azygos 
major  arches  over  the  right  bronchus,  and  the  aorta  over  the 
left,  while  the  interval  between  the  two  is  occupied  by  a  group 
of  bronchial  lymphatic  glands.  On  the  left  side  the  pulmonary 
artery  crosses  above  all  the  collateral  branches  of  the  bronchus, 
while  on  the  right  side  the  first  collateral  bronchus  lies  above 
the  artery,  and  the  others  below  it. 

Foreign  bodies,  small  enough  to  pass  the  glottis,  sometimes 
drop  into  the  trachea,  lodging  probably  about  the  bifurcation, 
and  giving  rise  to  dyspnoea  and  cough.  When  small  enough 
to  enter  the  bronchus,  it  is  generally  the  right  one  which  is 
affected,  owing  to  its  larger  size,  and  the  position  of  the 
septum,  which  lies  rather  to  the  left  of  the  middle  line. 

The  pleurae  are  closed  sacs  which  line  the  chest-walls 
(parietal)  and  the  surfaces  of  the  lungs  (visceral) .  They  consist 
of  elastic  and  connective  tissue,  lined  with  flat  endothelium, 
the  parietal  and  visceral  layers  being  in  contact,  save  for  the 
interposition  of  a  little  clear  serous  fluid  at  all  points,  except 
at  the  incisura  of  the  left  lung,  and  at  the  lower  and  anterior 
portion  on  both  sides  (pleural  sinuses). 

While  the  visceral  pleura  is  intimately  adherent  to  the  lung, 
the  parietal  pleura  is  generally  comparatively  free.  The 
cervical  portion  of  the  parietal  pleura  is  connected  to  the  spine 
and  first  rib  by  fibrous  bands  which  support  it :  the  costal 
portion,  which  is  the  strongest,  is  separated  from  the  chest- 
wall  by  a  layer  of  connective  tissue,  the  endothoracic  fascia ,  the 


THE  THORAX  169 

diaphragmatic  portion  is  fairly  adherent,  but  does  not  extend 
to  the  "bottom  of  the  groove  between  the  thoracic  wall  and 
diaphragm.  The  mediastinal  portion  is  loose  above  the  peri- 
cardium, and  extends  direct  from  sternum  to  spine.  Over 
the  pericardium,  however,  it  is  adherent,  and  it  is  invaginated 
over  the  root  of  the  lung  to  join  the  visceral  layer.  This 
dipping  in  of  the  parietal  pleura  to  meet  the  visceral  continues 
from  the  root  of  the  lung  to  the  base,  and  the  two  layers,  which 
thus  come  in  contact,  form  a  vertical  fold,  the  ligamentum 
latum  pulmonis.  The  LINES  OF  REFLECTION  of  the  pleura 
from  the  chest- wall  are  of  considerable  importance.  Anteriorly, 
on  the  right  side,  the  line  begins  opposite  the  interval  between 
the  two  heads  of  the  sterno-mastoid,  runs  down  and  inwards 
behind  the  sterno-clavicular  articulation,  to  meet  its  fellow 
at  the  manubrio-gladiolar  junction,  generally  a  little  to  the 
left  of  the  middle  line,  whence  it  descends  almost  vertically 
to  the  sixth  intercostal  space,  and  then  curves  outwards, 
becoming  continuous  with  the  costo-diaphragmatic  reflection. 
On  the  left  side  it  behaves  similarly,  save  that  at  the  level  of 
the  fourth  costal  cartilage  it  deviates  outwards  behind  the 
inner  extremities  of  the  fifth  and  sixth  intercostal  spaces, 
which  thus  are  in  contact  for  a  short  distance  with  the  peri- 
cardium. Below,  starting  from  the  sternal  end  of  the  sixth 
intercostal  space,  the  reflection  on  the  right  side  runs  down 
and  outwards,  crosses  the  junction  of  the  seventh  rib  and  its 
cartilage,  crosses  the  seventh  space  in  the  mammary  line,  and 
so  runs  down  to  the  tenth  rib  behind  the  midaxillary  line. 
Then  it  runs  inwards  to  the  vertebral  end  of  the  twelfth  rib. 
On  the  left  side  this  reflection  commences  behind  the  sixth 
costal  cartilage,  but  otherwise  resembles  the  right.  Generally 
speaking,  a  line  from  the  lower  end  of  the  gladiolus  over  the 
cartilage  of  the  ribs  to  the  lower  border  of  the  last  rib  indicates 
this  reflection  with  sufficient  accuracy.  Posteriorly,  the  pleurae 
extend  to  the  costo-vertebral  junctions.  The  lowest  part  of 
the  pleural  sac  is  posterior,  behind  the  twelfth  rib,  but  opera- 
tions on  the  pleura  at  this  part  are  rather  dangerous,  as, 
owing  to  the  rapid  arching  of  the  diaphragm,  a  trocar  intro- 
duced would  almost  certainly  penetrate  both  layers  of  pleura 
and  diaphragm,  and  enter  the  abdomen — probably  the 
stomach,  if  done  on  the  left  side.  It  is  well  to  remember, 
however,  that  the  lower  level  of  the  pleura  reaches  the  twelfth 


1 70  SURGICAL  ANATOMY 

rib,  even  when  that  rib  is  rudimentary,  and  occasionally  it 
descends  to  the  transverse  process  of  the  first  lumbar  vertebra, 
thus  rendering  it  liable  to  wounding  in  operations  on  the 
kidney  in  the  lumbar  region.  The  pleura  extends  further 
down  in  the  child  than  in  the  adult,  and  slightly  further  on 
the  left  side  than  on  the  right.  Normally,  except  at  the 
pleural  sinuses,  the  pleural  surfaces  are  in  contact  with  one 
another,  save  for  the  interposition  of  a  thin  layer  of  serous 
fluid.  As  a  result  of  the  smooth,  polished  surfaces  which  the 
pleurae  present  to  one  another,  and  the  intervening  thin  layer 
of  fluid,  the  force  of  cohesion  between  the  two  layers  is  very 
great.  This  force  is  not  merely  sufficient  to  counterbalance  the 
contractile  elasticity  of  the  lung  substance,  but  tends  to  extrude 
any  accumulatipn  of  fluid  which  may  exist  between  the  two 
surfaces.  Thus,  it  is  quite  safe  to  remove  two  or  three  ribs, 
and  expose  the  visceral  pleura ;  not  only  will  the  lung  not 
collapse,  but  if  there  be  a  recent  accumulation  of  fluid  between 
the  layers  this  will  be  expelled,  the  lung  being  pulled  out  to  its 
original  size  by  the  cohesive  force  acting  on  the  pleurae.  In 
some  cases,  due  possibly  to  forced  expiratory  efforts,  the  lung 
has  even  protruded  from  an  opening  in  the  chest  (hernia  of 
lung). 

Pneumothorax,  or  air  in  the  pleural  cavity,  is  generally 
produced  by  a  valve-shaped  wound,  as  in  some  cases  of  com- 
pound fracture  of  the  ribs,  the  respiratory  action  forcing  air 
in  between  the  layers  of  pleura,  and  so  separating  them.  In 
severe  cases  the  pneumothorax  may  be  so  great  as  to  threaten 
collapse  of  the  lung,  and  produce  urgent  dyspnoea.  In  such 
cases  the  wound  should  be  laid  freely  open,  thus  destroying 
the  valve  ;  the  chest-wall  compressed  so  as  to  express  the  air, 
and  restore  the  condition  of  cohesion  between  the  layers  of 
pleura,  when  the  lung  will  expand  to  its  normal  size.  Some- 
times it  is  sufficient  to  introduce  a  trocar  and  cannula,  leaving 
the  latter  in  situ.  It  is  noteworthy  that  in  some  cases  of 
wound  of  the  chest  involving  the  pleura  an  actual  bulging 
forwards,  or  hernia  of  the  lung,  has  occurred,  and  elaborate 
theories  have  been  advanced  to  account  for  such  phenomena. 
Where,  from  any  cause,  cohesion  is  destroyed,  collapse  of  the 
lung  may  occur  readily.  Thus,  wounds  of  the  pleura  affecting 
the  pleural  sinuses  are  particularly  prone  to  result  in  collapse,  air 
at  these  points  getting  most  readily  between  the  two  surfaces. 


THE  THORAX  171 

Emphysema  of  the  subcutaneous  tissues  frequently  results 
from  switch  valve-shaped  wounds  as  mentioned,  the  air  being 
pumped  by  the  respiratory  movements  into  the  tissues.  It 
may  also  arise  from  valved  superficial  wounds  which  do  not 
communicate  with  the  pleura  or  lung,  the  chest  movement 
supplying  the  pumping  action.  Pleural  effusions  sometimes 
result  in  soldering  of  the  two  surfaces  together.  On  the  other 
hand,  they  may  force  the  two  surfaces  apart,  and  produce 
grave  changes  in  the  serous  membranes.  This  is  well  seen  in 
empyema,  or  accumulation  of  pus  in  the  pleural  cavity,  which 
sometimes  is  of  great  size,  causing  bulging  of  the  chest- wall  on 
the  affected  side,  collapse,  more  or  less  complete,  of  the  lung, 
and  thickening  of  the  pleurae  and  roughness  of  their  surfaces. 
The  thickening  of  the  pleurae  tends  to  prevent  re-expansion  of 
the  lung,  while  the  roughness  of  the  surface  destroys  the  force 
of  cohesion,  thus  rendering  it  difficult  to  keep  the  lung 
expanded,  even  if  it  tends  to  do  so.  Empyemas,  however,  are 
frequently  localized,  the  two  layers  of  pleura  becoming 
soldered  round  the  periphery  by  fibrous  exudation.  A  similar 
soldering  frequently  prevents  the  formation  of  a  pneumo- 
thorax  in  cases  of  perforation  of  the  visceral  pleura  from 
tubercular  disease  of  the  lung.  An  untreated  empyema  may 
burst  through  the  chest- wall  or  into  the  lung  or  pericardium, 
or  sometimes  may  extend  into  the  abdomen  through  the 
internal  arcuate  ligament. 

Empyema  is  generally  treated  by  evacuation  through  the 
sixth  or  seventh  intercostal  space  in  front  of  the  posterior 
axillary  fold.  Incisions  made  lower  down  may  wound  the 
diaphragm,  or  even  penetrate  the  abdomen,  owing  to  oblitera- 
tion of  the  lower  portion  of  the  pleural  cavity  from  disease  ; 
and  even  if  this  should  not  occur,  the  diaphragm  frequently 
ascends  after  the  empyema  has  been  evacuated,  rendering  the 
communication  very  oblique.  Where  the  empyema  is  local- 
ized, its  site  is  generally  determined  by  percussion,  and  con- 
firmed by  an  exploring  needle.  The  operation  may  consist 
of  an  incision  along  the  intercostal  space,  keeping  near  the 
upper  border  of  the  lower  rib,  or  a  portion  of  rib  may  be  excised. 
As  already  stated,  however,  changes  frequently  occur,  after 
empyema  has  been  present  for  some  time,  in  the  pleura,  and 
disease  may  be  present  in  the  lung,  so  that  even  after  evacua- 
tion of  the  pus  the  lung  may  not  tend  to  expand. 


172  SURGICAL  ANATOMY 

In  such  cases  healing  is  very  slow,  the  chest  not  collapsing 
readily,  and  a  large  cavity  remaining  in  the  chest,  from  which 
there  is  a  continual  discharge.  In  these  circumstances  a 
thoracoplasty  is  performed — a  large  flap  being  raised  from  the 
chest-wall,  several  ribs  removed  subperiosteally,  the  abscess 
cavity  cleared  out  thoroughly,  and  the  two  refreshed  surfaces 
brought  into  contact  by  collapsing  the  chest- wall  (Estlander). 

The  LUNGS,  roughly  conical  in  shape,  occupy  the  thoracic 
cavity,  being  separated  from  one  another  by  the  mediastinum. 
The  right  lung  is  broader,  shorter,  and  slightly  larger  than  the 
left.  The  APEX  projects  into  the  root  of  the  neck,  corresponding 
posteriorly  to  the  spine  of  the  seventh  cervical  vertebra,  and 
anteriorly  to  a  point  nearly  i  inch  above  the  inner  end  of  the 
clavicle.  The  lines  of  the  anterior  borders  correspond  to 
those  of  the  pleural  reflections  already  given  (q.v.).  The 
anterior  border  of  the  left  lung  presents  a  notch  or  incisura 
corresponding  to  the  cardiac  apex,  which  is  thereby  left  un- 
covered by  lung.  The  BASES,  however,  do  not  reach  as  low 
as  the  pleurae.  Thus,  on  the  right  side  the  base  of  the  lung 
extends  from  the  sixth  intercostal  space  in  front  to  the  lower 
border  of  the  eighth  rib  in  the  axillary  line,  and  that  of  the 
tenth  rib  in  the  scapular  line,  and  then  runs  horizontally 
inwards  to  the  vertebral  extremity  of  the  eleventh  rib,  the 
lowest  level  reached  being  the  ninth  intercostal  space  in  front 
of  the  scapular  line.  The  lower  border  of  the  left  lung  is 
similar,  but  rather  lower.  In  consequence  of  the  pleurae 
descending  below  the  lower  limit  of  the  lung,  it  is  possible  to 
get  wounds  which  involve  the  pleura,  but  do  not  damage  the 
lung.  Both  lungs  present  a  deep  FISSURE,  which  commencing 
posteriorly  about  3  inches  below  the  apex,  opposite  the  third 
dorsal  spine,  extends  first  horizontally  on  a  level  with  the 
vertebral  extremity  of  the  spine  of  the  scapula,  and  then  is 
directed  downwards  and  forwards,  dividing  the  lung  into  TWO 
LOBES,  and  terminating  in  front  at  the  level  of  the  lower 
border  of  the  sixth  rib  just  in  front  of  the  mammary  line. 
The  right  lung  generally  presents  a  second  fissure,  which  divides 
the  upper  lobe  into  two.  It  thus  presents  THREE  LOBES. 
The  mediastinal  surface  of  each  lung  is  concave,  and  particu- 
larly on  the  left  is  deeply  indented  by  the  pericardium.  The 
left  lung  is  also  grooved  above  the  hilum  by  the  arch  of  the 
aorta  and  left  subclavian  artery,  while  behind  the  hilum  the 


THE  THORAX  173 

right  i^  grooved  by  the  vena  azygos  major  and  oesophagus, 
and  the  left  is  in  relationship  to  the  oesophagus  and  thoracic 
duct.  The  HILUM  is  situated  on  the  inner  surface,  rather 
above  and  posterior  to  the  centre  of  the  lung,  opposite  the  fifth, 
sixth,  and  seventh  dorsal  spines.  It  is  oval  in  section,  and  is 
continuous  below  with  the  ligamentum  latum  pulmonis.  The 
structures  forming  the  ROOT  OF  THE  LUNG  are  the  bronchus, 
pulmonary  artery,  and  three  pulmonary  veins,  the  artery  lying 
below  the  bronchus  on  the  right  side,  and  above  it  on  the  left, 
while  the  veins  on  both  sides  lie  below  the  other  structures. 
The  branches  of  the  pulmonary  vessels  follow  the  bronchi, 
break  up  into  fine  capillaries,  which  project  into  the  lumen  of 
the  alveoli,  thus  producing  the  oxygenation  of  the  blood, 
which  then  returns  by  the  pulmonary  veins  to  the  left  auricle. 
In  addition  to  the  structures  mentioned,  there  are  small 
bronchial  arteries  and  veins  and  lymphatic  glands,  pulmonary 
lymphatic  vessels  and  nerves,  and  a  small  amount  of  con- 
nective tissue.  The  bronchial  arteries  supply  the  lung  tissue, 
and  vary  from  one  to  three  for  each  lung,  being  derived  from 
the  aorta  or  an  intercostal  vessel.  They  lie  on  the  posterior 
surface  of  the  bronchus.  The  blood  is  returned  partly  by 
the  pulmonary  and  partly  by  the  bronchial  veins,  which  latter 
open  into  the  azygos  veins.  The  pulmonary  nerves  are 
derived  from  the  vagus  and  sympathetic. 

Wounds  of  the  lung  are  occasionally  met  with,  and  cases  are 
recorded  where  rupture  of  the  lung  has  occurred  without  either 
external  wound  or  fracture  of  the  ribs.  In  bleeding  from  the 
lung  the  blood  may  be  effused  into  the  tissue  of  the  organ, 
giving  rise  to  pulmonary  apoplexy,  or  into  the  alveolar  spaces, 
and  so  to  the  bronchi,  causing  hemoptysis,  or,  where  the 
visceral  pleura  is  wounded,  into  the  pleural  cavity,  causing 
hcemothorax.  In  cases  of  desperate  bleeding  from  the  lung, 
it  may  be  necessary  to  open  the  chest- wall,  and  collapse  the 
lung.  The  lung  is  frequently  affected  by  emboli  brought  to 
it  by  the  systemic  veins,  or  from  the  right  side  of  the  heart. 
These  get  arrested  in  the  pulmonary  capillaries,  and,  if  septic 
(as  would  be  the  case  when  conveyed  from  septic  sigmoid 
sinus  thrombosis),  give  rise  to  lung  abscesses,  or,  where  they 
have  been  detached  from  some  sarcomatous  tumour,  give 
rise  to  secondary  tumours  in  the  lung.  Thus,  the  lung  should 
be  carefully  examined,  where  extension  either  of  a  venous 


174  SURGICAL  ANATOMY 

septic  process  or  of  sarcoma  is  suspected.  Fat  emboli  from 
injury  to  the  medulla  of  bone,  and  air  emboli  from  wound  of 
one  of  the  large  veins  in  the  neck,  also  occur  in  the  lung,  and 
the  latter  frequently  give  rise  to  asphyxia. 

Where  from  any  cause — as,  for  instance,  in  mitral  or  aortic 
disease — the  return  flow  of  blood  from  the  lungs  is  obstructed, 
the  lung  becomes  greatly  engorged.  The  bronchial  vessels 
anastomose  with  the  pulmonary,  but  they  are  of  small  size, 
and  only  serve  to  supply  the  lung  tissue. 

Cavities  in  the  lung  arise  perhaps  most  frequently  from 
tubercular  disease,  but  may  also  be  caused  by  abscesses, 
or  gangrene,  following  pneumonia,  the  entrance  of  foreign 
bodies,  or  by  extension  from  the  liver.  Hydatid  cysts  are  also 
sometimes  met  with.  In  such  cases  a  pneumotomy  may  be 
performed  in  order  to  reach  and  drain  the  cavity.  Such  an 
operation  is  generally  best  performed  in  two  stages — the  first 
opening  the  pleural  cavity,  and  the  second,  after  the  pleurae 
have  become  soldered  round  the  edges,  opening  into  the  lung 
substance,  the  cautery  being  sometimes  used  for  this  purpose, 
where  serious  bleeding  is  feared.  On  the  other  hand,  where 
the  lung  is  affected — for  example,  by  a  primary  sarcomatous 
tumour— it  may  be  necessary  to  excise  a  portion,  or,  where  it 
is  riddled  with  tubercle,  it  is  occasionally  advisable  to  remove 
the  whole  lung.  This  operation  is  known  as  pneumonectomy, 
and  consists,  first,  in  the  removal  of  several  ribs,  as  in  Estlander  s 
operation,  and,  at  a  later  stage,  of  ligature  of  the  affected 
portion  and  its  removal,  or,  where  complete  extirpation  is 
required,  ligature  of  all  the  structures  at  the  root  of  the  lung, 
and  removal  of  the  lung  in  toto  (Macewen).  Such  an  operation 
on  a  healthy  lung  would  probably  cause  immediate  death 
of  the  patient,  but,  in  disease,  the  lung  is  almost,  if  not 
entirely,  functionless  at  the  time  of  its  removal,  and  good 
results  are  hence  obtained,  the  more  normal  lung  frequently 
benefiting  by  the  removal,  as  cross  infection  by  the  bronchi 
and  trachea  is  arrested. 

The  OESOPHAGUS  is  normally  about  10  inches  long  and 
|  inch  wide,  and  presents  two  constrictions,  one  at  the 
beginning,  and  the  other  at  the  point  where  it  is  crossed  by  the 
left  bronchus,  each  capable  of  admitting  an  instrument  i  inch 
in  diameter.  Foreign  bodies  are  most  apt  to  lodge  at  these 
points.  But  for  the  pylorus,  it  is  the  narrowest  and  one  of 


THE  THORAX  175 

the  most  muscular  portions  of  the  alimentary  tract.  It 
extends  from  the  termination  of  the  pharynx,  opposite  the 
sixth  cervical  vertebra,  to  the  cardiac  orifice  of  the  stomach, 
opposite  the  eleventh  dorsal  vertebra ;  presents  an  antero- 
posterior  curve  in  conformity  with  the  vertebral  curve,  and 
also  two  lateral  curves  to  the  left,  the  first  at  the  lower  portion 
of  the  neck  and  upper  portion  of  the  thorax,  and  the  second 
behind  the  pericardium,  where  it  also  passes  forwards  to 
reach  the  cesophageal  opening  in  the  diaphragm.  In  addition 
to  the  portion  in  the  neck,  thoracic,  diaphragmatic,  and 
abdominal  portions  are  described. 

In  the  thorax  it  lies  close  to  the  vertebral  column  in  the 
superior  mediastinum,  while  in  the  posterior  mediastinum  it 
comes  forward  into  contact  with  the  posterior  surface  of  the 
pericardium.  The  trachea  and  left  bronchus  also  lie  in  front. 
Behind  lie  the  longus  colli  muscle  and  vertebral  column  above, 
while  below  the  vena  azygos  major,  thoracic  duct,  and  aorta 
intervene  between  the  oesophagus  and  column.  On  the  left 
side  the  thoracic  duct,  pleura,  and  left  subclavian  artery  lie 
superiorly,  then  the  aorta,  and  again  the  pleura.  On  the 
right  side  lie  the  arch  of  the  azygos  vein  and  pleura.  The 
pne^tmo  gastric  nerves  form  with  the  sympathetic  the  oesophageal 
plexus  (plexus  guise) ,  and  then  pass  to  the  stomach  along  with 
the  oesophagus,  the  left  nerve  lying  in  front,  and  the  right 
behind . 

The  oesophagus  passes  through  the  diaphragm  very 
obliquely,  and  laterally  and  posteriorly  is  in  contact  with  the 
walls  of  the  orifice  for  a  distance  of  J  inch.  The  abdominal 
portion  is  possibly  \  inch  in  length. 

Dysphagia,  or  difficulty  in  swallowing,  may  be  due  to 
(i)  spasmodic  stricture  (oesophagismus)  ;  (2)  organic  stricture, 
which  may  be  fibrous  (resulting  perhaps  from  swallowing  a 
corrosive,  and  situated  generally  at  the  upper  part  of  the  tube, 
or  due  to  syphilis,  etc.),  or  may  be  carcinomatous  ;  (3)  pressure 
on  the  oesophagus  from  without,  as  by  a  tumour  or  aneurism  ; 
(4)  impaction  of  a  foreign  body. 

In  order  to  ascertain  the  condition  of  the  oesophagus  in  such 
conditions,  a  stethoscope  may  be  placed  over  the  back,  and  the 
patient  asked  to  swallow.  Normally  the  act  of  swallowing  is 
almost  silent,  whereas  in  stricture  a  sound  of  dripping,  as 
succeeding  drops  pass  the  stricture,  is  frequently  audible. 


176  SURGICAL  ANATOMY 

An  cesophageal  bougie  is  frequently  passed,  care  being  taken 
before  doing  so  to  exclude  the  possibility  of  aneurism,  which 
might  otherwise  be  ruptured.  In  passing  the  bougie  the  head 
should  be  flexed  forwards,  and  not  thrown  backwards,  so  as  to 
prevent  the  bougie  from  entering  the  larynx,  and  the  point 
guided  by  the  finger  past  the  back  of  the  throat.  False 
passages  may  be  formed  if  sufficient  gentleness  be  not  exer- 
cised. While  it  is  possible  to  attack  the  oesophagus  in  the 
thorax  from  the  back,  portions  of  ribs  being  resected,  and  the 
pleura  carefully  avoided,  it  is  generally  desirable  in  cases  of 
cesophageal  stricture  to  alleviate  the  condition  by  performing 
a  gastrostomy. 


SECTION  III 
ABDOMEN  AND  PELVIS 

THE    ABDOMEN 

THE  abdomen  is  bounded  above  by  the  ensiform  cartilage  and 
costal  arches  ;  below  by  the  crest  of  the  ilium,  Poupart's 
ligament,  and  the  crest  and  symphysis  pubis  ;  and  behind  by 
the  lumbar  spine.  For  convenience  it  is  generally  arbitrarily 
divided  into  nine  sections  by  two  vertical  and  two  horizontal 
lines.  The  two  vertical  lines  run  upwards  from  the  centre  of 
Poupart's  ligament  on  either  side,  while  the  upper  horizontal 
line  runs  across  at  the  level  of  the  most  dependent  portion 
anteriorly  of  the  thoracic  framework  (tenth  costal  cartilages), 
and  the  lower  at  the  highest  point  of  the  iliac  crest  (about 
2j  inches  behind  the  anterior  superior  spine).  The  three 
upper  divisions  so  obtained  consist  of  a  middle  epigastric 
division,  and  right  and  left  hypochondriac  regions  ;  the  three 
central,  of  a  middle  umbilical  and  two  lateral  lumbar  regions  ; 
and  the  three  lower  of  a  middle  hypogastric,  and  two  lateral 
iliac  regions. 

THE  ABDOMINAL  PARIETES. 

The  skin  of  the  abdomen  is  thin,  smooth,  and  movable. 
In  certain  abdominal  affections,  such  as  ascites,  or  in  preg- 
nancy, the  skin  becomes  stretched  and  glazed,  and  presents 
dark  horizontal  marks  from  stretching  of  the  connective  tissue 
bundles.  On  removal  of  the  distending  cause,  these  present 
a  pale  cicatricial  appearance,  and  are  known  as  linece 
albicantes. 

The  subcutaneous  tissues  consist  of  two  layers,  a  superficial 

!/7  12 


178  SURGICAL  ANATOMY 

continuous  with  the  general  subcutaneous  fatty  layer  or 
panniculus  adiposus,  which  varies  greatly  in  amount  in  different 
individuals,  particularly  in  the  parts  below  the  umbilicus,  and 
a  deeper,  less  fatty  layer,  which  constitutes  the  deep  layer  of 
superficial  fascia,  and  which  is  attached  below  to  the  crest  of 
the  ilium  and  Poupart's  ligament,  but  is  continued  over  the 
penis  and  scrotum  to  the  perinseum,  where  it  forms  Colles' 
fascia.  Thus,  extravasated  urine  may  find  its  way  up  on  to 
the  abdomen,  being  limited  to  one  side,  however,  by  the 
median  attachment,  while  it  is  kept  from  the  thigh  by  the 
attachment  to  Poupart's  ligament. 

In  very  stout  persons  two  deep  transverse  furrows  run  across 
the  abdomen,  one  at  the  level  of  the  umbilicus,  which  is 
thereby  concealed,  and  the  other  just  above  the  pubic  fat. 
The  point  of  intersection  of  this  latter  line  with  the  linea  alba 
indicates  the  position  for  the  introduction  of  the  trocar  in 
tapping  the  bladder  above  the  pubes. 

The  anterior  abdominal  wall  is  composed  of  the  two  recti 
muscles  in  front,  and  laterally  of  three  muscular  planes.  The 
LINEA  ALBA  forms  a  vertical  median  furrow,  marking  the  inter- 
val between  the  recti  muscles,  which  are  generally  slightly 
separated  above  the  umbilicus,  but  close  together  below  it. 
Hence  the  line  only  extends  from  the  ensiform  to  the  umbilicus, 
or  slightly  beyond  it.  Along  this  line  the  abdominal  wall  is 
thin,  aponeurotic,  and  free  from  bloodvessels,  and  accordingly 
it  is  a  favourite  site  for  abdominal  incisions.  Lying  under  it 
from  above  downwards  are  the  left  lobe  of  the  liver,  the  stomach 
when  distended,  the  transverse  colon  (generally  above  the 
umbilicus,  but  very  variable),  the  great  omentum  covering  the 
small  intestines,  and  the  bladder  when  distended.  Spaces 
sometimes  exist  in  the  linea  alba,  through  which  small  masses 
of  subperitoneal  fat  may  project  and  simulate  irreducible 
herniae,  and  ventral  hernia  do  occasionally  protrude  through 
it.  The  umbilicus  is  nearer  the  pubes  than  the  xiphoid,  and 
corresponds  to  the  interval  between  the  third  and  fourth  lumbar 
vertebrae.  Normally  it  is  above  the  central  point  of  the  whole 
body.  The  parts  are  supplied  with  blood  by  small  branches  from 
the  internal  mammary  and  lower  intercostals  above,  and  by 
three  branches  of  the  femoral  (superficial  epigastric,  circumflex 
iliac,  and  external  pudic)  below,  together  with  twigs  from  the 
lumbar  arteries  and  perforating  branches  of  the  deep  epigastric. 


THE  ABDOMEN  179 

the  superficial  veins  are  of  importance,  as  connecting 
links  between  the  systemic  and  portal  systems.  Thus,  the 
superficial  epigastric  vein  is  connected  to  the  portal  vein  by  its 
communication  with  the  deep  epigastric  vein  at  the  umbilicus, 
and  so  with  the  para-umbilical  veins  which  run  along  the 
round  ligament  to  the  liver,  where  they  join  the  portal.  A 
small  vein  sometimes  runs  vertically  from  the  umbilicus  to  the 
ensiform,  connecting  the  para-umbilical  with  the  internal 
mammary  vein.  In  cases  of  portal  obstruction  the  flow  of 
blood  through  these  veins  may  be  greatly  increased,  and  in 
consequence  they  may  become  distended  and  somewhat 
varicosed,  the  condition  being  known  as  Caput  Medusa.  The 
long  superficial  thoracico-epigastric  vein  communicates  below 
with  the  femoral  or  superficial  epigastric,  and  above  with  the 
long  thoracic,  and  is  sometimes  greatly  dilated,  especially 
when  there  is  obstruction  of  the  vena  cava.  Its  valves  are 
so  arranged  as  to  direct  the  blood  from  its  upper  part  to  the 
axilla,  and  from  its  lower  part  to  the  thigh. 

The  superficial  abdominal  lymphatics  drain  the  portions 
under  the  umbilicus  to  the  inguinal  glands,  and  those  above 
the  umbilicus  to  the  axillary  glands. 

The  LINEA  SEMILUNARIS  marks  the  outer  boundary  of  each 
rectus  muscle,  and  corresponds  to  the  splitting  of  the  internal 
oblique  aponeurosis  to  enclose  the  rectus.  It  extends  from  the 
tip  of  the  ninth  costal  cartilage  in  a  slight  curve,  with  the  con- 
vexity outwards,  toward  the  spine  of  the  pubes,  passing  about 
3  inches  outside  the  umbilicus.  It  disappears  some  distance 
above  the  pubic  spine.  Here,  as  in  the  case  of  the  linea  alba, 
the  abdominal  wall  is  thin  and  comparatively  bloodless,  and 
accordingly  the  incision  for  certain  operations  on  the  gall- 
bladder, stomach,  and  kidney  is  made  through  it.  The  RECTI 
MUSCLES  extend  from  the  xiphoid,  and  fifth,  sixth,  and  seventh 
costal  cartilages  to  the  crest  of  the  pubes  and  symphysis. 
Each  presents  two  or  more  linece  transverse,  or  transverse 
tendinous  intersections,  the  first  being  situated  about  the 
lowest  level  of  the  tenth  rib,  or  about  4  inches  above  the 
second,  which  is  situated  about  the  level  of  the  umbilicus.  A 
spasmodic  contraction  of  one  of  these  sections  of  the  rectus 
muscle,  which  occurs  most  frequently  in  hysterical  subjects, 
has  been  mistaken  for  a  projecting  abdominal  tumour.  The 
sheath  of  the  rectus  muscle  over  three-fourths  of  the  abdominal 

12 — 2 


i8o  SURGICAL  ANATOMY 

wall  is  derived  from  the  aponeurosis  of  the  internal  oblique, 
which  splits  at  the  linea  semilunaris  to  enclose  it,  the  anterior 
division  being  joined  by  the  aponeurosis  of  the  external 
oblique,  while  the  posterior  division  is  joined  by  that  of  the 
transversalis.  Below  the  level  of  a  point  midway  between  the 
umbilicus  and  pubic  crest,  however,  the  aponeurosis  of  the 
internal  oblique  does  not  split,  but,  accompanied  by  that  of  the 
transversalis,  passes  entirely  in  front  of  the  rectus  muscle,  to 
form  the  CONJOINED  TENDON.  The  sheath,  therefore,  is 
deficient  posteriorly  from  this  point  downwards,  the  lowest 
limit  of  the  posterior  layer  forming  a  crescentic  margin,  called 
the  fold  of  Douglas.  Further,  the  aponeurosis  of  the  external 
oblique  also  separates,  and  becomes  distinct  from  the  other 
layers  about  this  level.  The  portion  of  the  rectus  which  lies 
on  the  chest-wall  is  only  covered  anteriorly  by  a  layer  of 
aponeurosis  derived  from  the  external  oblique.  The  sheath 
of  the  rectus  contains  the  deep  epigastric  and  superior  epi- 
gastric arteries,  and  the  terminations  of  the  six  lower  inter- 
costal and  last  dorsal  nerves. 

A  separation  of  the  recti,  rarely  extreme,  occasionally  occurs 
below  the  umbilicus,  particularly  after  numerous  pregnancies. 
The  muscle  is  sometimes  torn  by  muscular  or  other  violence, 
the  opisthotonos  of  tetanus,  etc. 

The  pyramidalis  muscle  lies  in  front  of  the  rectus,  and  within 
its  sheath.  It  is  triangular  in  shape,  arising,  when  present, 
from  the  crest  of  the  pubes  to  be  inserted  into  the  linea  alba. 

PGUP  ART'S  LIGAMENT  is  indicated  by  a  fold  running  in  a 
slight  curve  with  the  convexity  downwards  from  the  anterior 
superior  spine  of  the  ilium  to  the  spine  of  the  pubes.  PETIT' s 
TRIANGLE  is  situated  above  the  middle  cf  the  iliac  crest,  and 
is  formed  by  the  external  oblique  in  front,  and  the  latissimus 
dorsi  behind,  while  its  floor  is  formed  by  the  internal  oblique. 
Lumbar  abscesses,  and  occasionally  herniae,  may  point  through 
the  triangle. 

In  addition  to  the  recti  muscles,  the  anterior  abdominal 
wall  presents  the  external  and  internal  oblique  and  trans- 
versalis muscles.  It  is  important  to  remember  the  direction 
of  the  fibres  of  these  muscles,  as  in  many  abdominal  operations 
it  is  desirable  to  split  the  fibres  of  the  muscles  rather  than  cut 
them.  The  three  sets  of  fibres  present  a  Union  Jack  on 
the  abdomen ;  those  of  the  external  oblique  run  downwards 


THE  ABDOMEN 


181 


and  inwards  in  the  direction  of  the  finge:3  when  the  hand  is 
laid  naturally  on  the  front  of  the  abdomen,  those  of  the 
internal  oblique  run  at  right  angles  to  those  of  the  external, 
while  those  of  the  transversalis,  as  the  name  implies,  run 
transversely.  The  EXTERNAL  OBLIQUE  arises  from  the  eight 
lower  ribs,  and,  becoming  tendinous,  is  inserted  into  the  outer 
lip  of  the  iliac  crest,  Poupart's  ligament,  pubic  spine,  front  of 


FIG.   19. — SCHEME  OF  ABDOMINAL  MUSCLES  (IN  SECTION). 

i.   Kxternal  oblique.  5.  Latissimus  dorsi. 

•2.   Internal  oblique.  6.  Psoas. 

3.  Transversalis.  7.  Quadratus  lumborum. 

4.  Rectus.  8.  Erector  spinae. 

The  semicircle  presents  the  arrangement  of  the  abdominal  muscles  below  the  level  of  the 
umbilicus.  Note  anteriorly  how  the  tendon  of  the  internal  oblique  splits  to  enclose  the  rectus 
muscle,  the  anterior  portion  being  joined  by  the  tendon  of  the  external  oblique  and  the 
posterior  portion  by  the  tendon  of  the  transversalis.  The  smaller  diagram  presents  the 
arrangement  of  these  parts  about  an  inch  above  the  pubes.  Note  how  the  tendon  of 
the  external  oblique  is  separate  and  distinct  from  the  others  ;  how  the  tendon  of  the  internal 
oblique  does  not  split  to  enclose  the  rectus,  but,  fused  with  that  of  the  transversalis  to  form  the 
conjoined  tendon,  passes  in  front  of  the  rectus. 

the  symphysis  (some  fibres  crossing  to  the  opposite  side  at 
this  point),  and  linea  alba,  or  anterior  sheath  of  the  rectus. 
The  INTERNAL  OBLIQUE  arises  from  the  lumbar  aponeurosis, 
anterior  half  of  the  iliac  crest,  and  outer  half  of  Poupart's 
ligament,  and  is  inserted  into  the  last  three  ribs,  and,  splitting 
to  form  the  rectus  sheath,  into  the  seventh,  eighth,  and  ninth 
costal  cartilages  and  linea  alba.  The  fibres  arising  from 


182  SURGICAL  ANATOMY 

Poupart's  ligament  go  chiefly  to  form  the  conjoined  tendon, 
along  with  the  transversalis.  A  few  of  the  lower  fibres,  ho\v- 
ever,  are  continued  down  in  loops  over  the  cord  and  testicle, 
and  are  finally  inserted  into  the  pubic  spine  and  surrounding 
fascia.  These  fibres  are  generally  named  the  CREMASTER 
MUSCLE,  and  in  the  female,  being  chiefly  represented  by  fascia, 
constitute  the  CREMASTERIC  FASCIA.  The  TRANSVERSALIS 
muscle  arises  from  the  under  surfaces  of  the  lower  six  ribs,  the 
lumbar  fascia,  the  anterior  half  of  the  inner  lip  of  the  iliac 
crest,  and  the  outer  one-third  of  Poupart's  ligament.  It 
is  inserted  into  the  posterior  sheath  of  the  rectus,  and  so  to 
the  linea  alba  and  ensiform  ;  and  the  lower  fibres,  joined  by 
those  of  the  internal  oblique,  form  the  conjoined  tendon. 
These  three  muscles  are  separated  from  one  another  by  loose 
connective  tissue,  in  which  pus  or  other  fluid  may  easily  spread 
to  the  various  insertions  enumerated  above,  intraparictal 
liernice  also  occurring  occasionally  between  the  layers.  The 
deep  surface  of  the  transversalis  *is  lined  by  the  thin  TRANS- 
VERSALIS FASCIA.  The  transversalis  fascia  lines  the  inner 
surface  of  the  abdominal  wall,  being  best  developed  in  the 
lower  abdomen  and  in  front,  and  becoming  lost  above  upon 
the  diaphragm,  and  posteriorly  upon  the  fasciae  of  the  quad- 
ratus  lumborum  and  psoas.  Below  the  semilunar  fold  of 
Douglas  it  is  in  intimate  contact  with  the  rectus  until  close 
to  the  symphysis,  where  it  separates,  leaving  a  triangular 
interval  occupied  by  fatty  tissue.  Internally,  it  is  attached 
to  the  crest  of  the  pubes,  and  to  Gimbernat's  ligament,  and 
externally  to  the  outer  half  of  Poupart's  ligament,  but 
between  these  points  it  extends  into  the  thigh,  forming  the 
anterior  layer  of  the  femoral  sheath.  The  EXTRA-  or  SUB- 
PERITONEAL  TISSUE  is  a  layer  of  fat-laden  connective  tissue 
which  separates  the  fasciae  of  the  abdominal  muscles  from 
the  peritoneum  (parietal  portion),  and  also  extends  into  the 
various  mesenteries  (visceral  portion).  It  is  further  continued 
on  the  vessels,  nerves,  etc.,  which  pass  out  from  the  abdomen. 
In  this  loose  tissue  abscesses  arising  from  abdominal  organs, 
particularly  such  as,  like  the  kidney,  are  only  partially  covered 
by  peritoneum,  may  readily  spread.  Abscesses  arising  from 
the  appendix,  kidney,  and  gall-bladder  may  also  spread  in  this 
layer.  The  laxity  cf  this  tissue  used  also  to  be  taken  advan- 
tage of  in  ligaturing  the  external  and  common  iliac  vessels 


THE  ABDOMEN  183 

without  opening  the  peritoneum,  the  latter  membrane  being 
pushed*  aside  until  the  vessels  were  reached. 

The  abdominal  wall  is  supplied  by  the  lower  seven  dorsal 
and  first  lumbar  NERVES,  which  run  forwards  and  downwards 
between  the  internal  oblique  and  transversalis.  Thus,  the  sixth 
dorsal  supplies  the  region  of  the  ensiform  cartilage,  the  tenth 
dorsal  the  umbilicus,  and  the  first  lumbar  the  pubis,  the  various 
areas  overlapping  one  another.  These  nerves  supply  both 
the  skin  and  the  underlying  muscles,  and  thus  any  irritation 
of  the  skin,  such  as  cold  or  a  blow,  produces  an  immediate 
contraction  of  the  muscles,  which  thus  tend  to  protect  the 
underlying  viscera.  Further,  the  first  six  of  these  nerves  are 
intercostal  nerves,  and  control  the  respiratory  movements  to 
a  considerable  extent,  so  that  when  the  skin  of  the  abdomen 
is  irritated  there  is  a  tendency  to  inspiration  and  fixation  of 
the  lower  portion  of  the  chest.  When,  therefore,  it  is  desired 
to  subject  the  abdomen  to  deep  palpation,  the  hands  should 
be  warm,  and  should  be  laid  flat  on  the  surface,  the  fingers 
afterwards  being  gently  pressed  in.  On  the  other  hand,  these 
same  nerves  are  associated  with  the  abdominal  viscera  through 
the  sympathetic  system,  and  thus  in  painful  affections  of  these 
viscera  there  is  generally  rigidity  of  the  abdominal  muscles, 
sometimes  very  marked,  the  respiration  being  entirely  thoracic, 
while  the  pain  is  referred  along  these  nerves  to  the  parietes, 
generally  in  the  region  of  the  umbilicus,  the  skin  frequently 
being  tender  to  the  touch. 

The  abdominal  viscera  are  connected  through  the  solar 
plexus,  splanchnic  nerves,  and  rami  communicantes  with  the 
segments  of  the  spinal  cord  from  the  sixth  dorsal  to  the  first 
lumbar,  while  the -pelvic  viscera  are  connected  with  those 
from  the  fifth  lumbar  to  the  third  sacral  through  the  nervi 
errigentes.  (It  will  be  noted  that  the  second  to  the  fourth 
lumbar  nerves  have  no  visceral  connections.) 

The  stomach  communicates  with  the  sixth  to  the  ninth 
dorsal,  the  liver  and  gall-bladder  with  the  seventh  to  the  tenth 
dorsal,  the  intestine  with  the  ninth  to  the  twelfth  dorsal,  and 
the  testicle  and  ovary  with  the  tenth  dorsal.  The  kidney  and 
ureter  communicate  with  the  tenth  to  the  twelfth  dorsal  and 
the  first  lumbar  ;  the  uterus  with  the  tenth  to  the  twelfth 
dorsal,  first  lumbar,  and  third  and  fourth  sacral  ;  the  rectum 
with  the  second  to  the  fourth  sacral. 


I  $4 


SURGICAL  ANATOMY 


It  is  important  to  remember  that  in  spinal  injuries  and 
disease,  such  as  tubercle  or  tumour  formation,  pain  may  be 
referred  to  the  parietes  over  certain  organs  which  may  accord- 


17--- 


FIG.  20. — CUTANEOUS  NERVES  OF  THE  TRUNK     ANTERO-LATERAL  VIEW 

(After  Henle.) 
1-12.  Anterior  cutaneous.  2-12.  Lateral  cutaneous. 

13.  Intercosto-humeral.  16.   Iliac  branch  of  ilio-hyppgastric. 

14.  Additional  intercosto-humeral.  17.  Hypogastric  branch  of  ilio-hypogastric. 

15.  Lateral  cutaneous  of  twelfth  thoracic. 

ingly  be  presumed  to  be  diseased.  Thus,  a  sense  of  abdominal 
constriction,  amounting  in  some  cases  to  actual  pain,  and 
referred  to  the  region  of  the  umbilicus,  may  arise  in  Pott's 


THE  ABDOMEN  185 

disease,  and  be  mistaken  for  intestinal  colic,  while  pain  from 
a  lesion  lower  down  might  be  mistaken  as  pointing  to  some 
affection  of  the  kidney  or  bladder. 

The  ilio-hypogastric  and  ilio-inguinal  nerves  are  derived  from 
the  first  lumbar,  the  former  supplying  part  of  the  skin  over  the 
ilium  and  over  the  external  ring,  while  the  latter  runs  forward 
under  the  external  oblique  to  supply  the  skin  of  the  scrotum  or 
labium  majus,  and  of  the  upper  and  inner  aspect  of  the  thigh. 

DEEP  VESSELS. — The  two  lower  intercostal,  the  subcostal,  and 
the  four  lumbar  arteries,  run  forward  between  the  transversalis 
and  internal  oblique,  and  anastomose  with  the  internal  mam- 
mary, deep  epigastric,  and  circumflex  iliac,  and  with  one  another. 

The  DEEP  EPIGASTRIC  arises  from  the  external  iliac  just 
above  Poupart,  and  to  the  inside  of  the  internal  abdominal 
ring,  and  runs  upwards  and  inwards  along  with  its  venae 
comites  to  pierce  the  fascia  transversalis,  and  enter  the 
rectus  sheath  above  the  fold  of  Douglas,  where  it  anastomoses 
with  the  internal  mammary,  which  anastomosis  is  of  import- 
ance in  ligature  of  the  common  or  external  iliac. 

The  DEEP  CIRCUMFLEX  ILIAC  arises  from  the  outer  side  of  the 
external  iliac,  nearly  opposite  to  the  deep  epigastric,  and, 
accompanied  by  its  venae  comites,  runs  in  a  groove  between 
the  transversalis  and  iliac  fasciae  outwards,  just  above 
Poupart's  ligament,  to  the  anterior  superior  spine,  where  it 
pierces  .the  transversalis,  and  runs  back  and  breaks  up, 
anastomosing  with  the  lower  intercostal  and  lumbar  arteries, 
and  the  ilio-lumbar  of  the  internal  iliac.  It  should  be  noted 
that  not  merely  do  these  vessels  anastomose  with  one  another, 
but  that  they  also  anastomose  with  the  vessels  supplying 
some  of  the  abdominal  viscera.  Thus,  the  lower  intercostal 
arteries  communicate  with  the  hepatic,  renal,  and  suprarenal 
arteries,  while  the  lumbar  and  circumflex  iliac  vessels  anasto- 
mose with  those  supplying  the  ascending  and  descending  colon. 

The  umbilicus  is  the  last  portion  of  the  abdominal  cavity  to 
become  closed,  and  through  it,  by  means  of  the  umbilical 
cord  during  foetal  life,  the  embryo  receives  nourishment  and 
oxygen,  from  the  yolk-sac  and  blood-supply,  while  excreted 
matter  passes  out  along  the  allantois.  In  the  embryo  of 
three  months  all  the  abdomen,  save  the  umbilical  ring,  has 
closed,  and  through  this  fibrous  ring  the  cord  passes.  Exter- 
nally the  cord  is  invested  with  amnion,  which  latter  becomes 


1 86  SURGICAL  ANATOMY 

continuous  with  the  abdominal  wall  at  the  umbilicus,  and  the 
structures  contained  within  it  are  (a)  TWO  ARTERIES  AND  ONE 
VEIN.  These  structures  separate  at  the  umbilicus,  the  arteries 
running  downwards  and  outwards,  one  on  either  side,  to 
become  the  common  iliac  trunks,  while  the  vein  runs  upwards 
to  the  liver.  In  true  congenital  umbilical  hernia  the  bowel 
generally  passes  out  between  these  three  structures  which  are 
spread  over  its  surface.  After  birth  the  two  arteries  become 
the  OBLITERATED  HYPOGASTRic  ARTERIES,  while  the  vein  forms 
the  ROUND  LIGAMENT  of  the  liver.  As  the  abdomen  increases 
in  size,  these  structures  do  not  tend  to  grow  along  with  it,  and 
thus  the  umbilicus  is  pulled  inwards  and  downwards,  carrying 
the  vein  along  with  it,  so  that  in  the  adult  the  upper  segment 
of  the  umbilicus  is  left  free,  (b)  Up  to  the  third  month  the 
midgut  is  in  communication  with  the  yolk-sac,  or  umbilical 
vesicle,  by  the  VITELLO-INTESTINAL  DUCT,  the  loop  of  bowel, 
which  is  known  as  the  umbilical  loop,  lying  outside  the  body 
wall  at  first.  About  the  third  month,  however,  this  com- 
munication should  disappear,  and  the  bowel  retire  within  the 
abdomen.  Where  for  any  reason  the  bowel  does  not  retire,  a 
congenital  hernia  is  formed.  Sometimes,  on  the  other  hand,  a 
portion  of  the  duct  may  persist.  This  persistent  portion 
forms  what  is  known  as  Meckel's  diverticulum,  which  varies  in 
length,  and  arises  from  the  ileum  from  i  to  4  feet  from  the  ileo- 
caecal  valve.  Sometimes  the  free  end  of  the  diverticulum  is 
connected  to  the  umbilicus  by  a  fibrous  cord  (which  is  an 
occasional  cause  of  strangulation),  and  in  other  cases  the  duct 
remains  patent  right  up  to  the  umbilicus,  causing  a  fczcal  fistula. 
Cystic  adenomata  occasionally  occur  about  the  umbilicus  in 
connection  with  the  remains  of  the  duct,  (c)  The  ALLANTOIS 
grows  out  from  the  ventral  aspect  of  the  hind  gut,  and  when 
the  placenta  is  formed  its  vessels  convey  the  blood  between 
the  embryo  and  the  placenta.  Normally  the  allantois  shrivels, 
save  its  lower  end,  which  forms  the  urinary  bladder.  A  fibrous 
cord  running  up  in  the  middle  line  between  the  two  hypo- 
gastric  arteries  from  the  apex  of  the  bladder  to  the  umbilicus 
represents  the  shrivelled  intra-abdominal  stalk,  which  is  known 
as  the  URACHUS.  Sometimes  the  urachus  remains  patent, 
giving  rise  to  a  urinary  fistula  at  the  umbilicus.  In  other  cases 
the  urachus  becomes  obliterated  at  either  extremity,  while  the 
central  portion  becomes  distended,  forming  a  cyst  of  the 


THE  ABDOMEN  187 

urachus-  (d)  The  cord,  as  stated  above,  is  covered  by  a  layer  of 
amnion,  and,  in  addition  to  the  structures  enumerated,  contains 
a  mass  of  fibro-myxomatous  tissue,  known  as  Whartoris  jelly. 

Three  forms  of  HERNIA  may  be  met  with  at  the  umbilicus, 
(i)  Congenital.  This  may  be  associated  with  some  grave 
defect  in  the  abdominal  wall,  the  viscera  remaining  exposed,  or 
covered  by  only  a  thin  membrane.  Sometimes  the  viscera 
lie  outside  the  abdominal  cavity  (ectopia  or  exomphalos).  In 
other  cases  the  abdominal  wall  may  be  normal,  but  a  loop  of 
bowel,  as  already  described,  may  project  within  the  cord  for 
some  distance  beyond  the  umbilicus,  and  thus  be  liable  to 
ligature  with  the  cord,  giving  rise  to  intestinal  obstruction. 
Where  such  herniae  are  recognized,  and  do  not  easily  return 
to  the  abdomen,  great  care  must  be  taken  in  cutting  the  parts 
at  the  umbilicus  to  increase  the  aperture,  as  important 
structures  practically  surround  the  bowel.  (2)  A  small 
infantile  form  of  umbilical  hernia  is  not  infrequently  met  with, 
the  condition  arising  soon  after  birth  from  stretching  of  the 
umbilicus.  It  is  generally  cured  by  the  steady  application  of 
pressure  for  some  time.  (3)  As  already  stated,  the  umbilical 
scar  tends  to  become  invaginated  and  pulled  downwards  as  the 
patient  grows,  even  the  vein  arising  from  the  lower  border  in 
the  adult.  Thus,  in  acquired  umbilical  hernia  the  protrusion 
takes  place  above  these  structures,  through  the  upper  portion 
which  is  comparatively  weak  and  thin.  A  further  possible 
cause  for  hernia  selecting  this  upper  portion  is  the  occasional 
presence  of  an  umbilical  canal,  which  is  a  small  median  diverti- 
culum  of  the  fascia  transversalis,  lined  by  peritoneum,  the 
mouth  of  which  is  directed  upwards,  while  the  blind  extremity 
is  directed  toward  the  upper  margin  of  the  umbilicus.  Such 
herniae  are  generally  loculated  and  thin-walled,  the  peritoneum 
being  very  adherent  to  the  skin. 

The  INGUINAL  REGION  is  of  much  importance  surgically 
on  account  of  the  frequency  with  which  hernia  occurs  in  it. 
The  arrangement  of  the  abdominal  muscles  has  already  been 
given,  and  attention  will  now  be  directed  to  the  parts  particu- 
larly concerned  in  hernia.  The  chief  of  these  is  the 
INGUINAL  CANAL — a  slit,  triangular  in  section,  between  the 
conjoined  tendon  behind  and  the  external  oblique  in  front, 
with  Poupart's  ligament  as  a  base — which  commences  in  the 
abdomen  at  the  internal  ring,  and  ends  externally  over  the 


1 88 


SURGICAL  ANATOMY 


crest  of  the  pubes  at  the  external  ring.  It  transmits  the  cord 
in  the  male,  and  the  round  ligament  in  the  female,  and,  normally, 
the  whole  space  of  the  canal  is  occupied  by  these  structures. 
The  parts  are  best  studied  from  the  abdominal  side,  and  for 
this  purpose  we  shall  suppose  in  the  first  place  that  peritoneum, 
subperitoneal  fat,  transversalis  fascia,  and  other  structures 
have  been  removed,  leaving  the  bones,  ligaments,  and  muscles 
exposed,  and  that  the  abdominal  wall  is  viewed  from  behind. 
POUPART'S  LIGAMENT  is  a  strong  fibrous  band,  which  runs 
from  the  anterior  superior  spine  to  the  spine  of  the  pubes. 
GIMBERNAT'S  LIGAMENT  is  a  reflection  from  its  inner,  or  pubic 


FIG.  21. — STEREOGRAM  OF  ABDOMINAL  WALL,  GIVING  AN  EXAGGERATED 
VIEW  OF  THE  INGUINAL,  FEMORAL,  AND  OBTURATOR  CANALS.  (For 
references,  see  Fig.  22.) 

The  figure  may  be  viewed  through  an  ordinary  stereoscope  or  may  be  seen  stereoscopically 
by  holding  it  about  2  f-et  from  the  eyes  (for  normal  vision),  relaxing  the  accommodation 
(the  pupils  meanwhile  dilating),  and  then  slightly  converging  the  eyes.  Three  figures  will 
be  seen,  of  which  the  central  one  is  stereoscopic.  A  piece  of  card  of  the  necessary  length 
extending  up  vertically  from  the  interspace  between  the  two  figures  to  the  nose  of  the  viewer 
facilitates  the  operation.  The  figures  must  be  equally  lit  while  viewing. 

end,  on  to  the  ilio-pectineal  line,  which  fills  in  the  angle  between 
Poupart  and  the  bone,  and  which  presents  a  crescentic  free 
border.  It  should  be  borne  in  mind  that  the  ILIO-PECTINEAL 
LINE  runs  not  merely  outwards,  but  also  backwards — out,  that 
is  to  say,  from  the  plane  of  a  diagram  toward  the  observer— 
as  otherwise  this  point  is  apt  to  lead  to  confusion.  The 
TRANSVERSALIS  MUSCLE  arises  from  the  outer  one-third  of 
Poupart,  while  the  INTERNAL  OBLIQUE  arises  from  the  outer 
half  of  Poupart,  and  thus  part  of  both  of  these  muscles  is  seen. 
They  rise  from  Poupart,  arch  over,  and  then,  fusing  to  form 
the  CONJOINED  TENDON,  pass  almost  directly  downwards,  to 
be  inserted  into  (a)  the  crest  of  the  pubes,  in  front  of  the  rectus 


THE  ABDOMEN  189 

(which,  therefore,  hides  this  portion  from  view),  but  behind  the 
external  oblique  ;  (b)-  spine  of  the  pubes ;  and  (c)  the  first  \  inch 
of  the  ilio-pectineal  line  along  with  but  behind  Gimbernat's 
ligament.  Thus,  this  latter  portion  of  the  conjoined  tendon 
does  not  lie  in  the  plane  of  a  diagram,  but  projects  outwards 
and  backwards  from  it  (see  stereogram) .  The  fibres  of  the 
transversalis  and  internal  oblique,  as  just  stated,  arch  above 
Poupart  between  their  origin  from  it  and  their  insertion  as 
conjoined  tendon,  and  through  this  arch  the  fibres  of  the 
EXTERNAL  OBLIQUE  can  be  seen,  as  this  muscle  arises  from  the 
whole  extent  of  Poupart's  ligament.  But  for  the  external 
oblique,  there  would  be  an  aperture  through  the  wall  at  this 
point.  If  the  finger  be  passed  through  this  arch  downwards 
and  inwards  toward  the  middle  line,  between  the  conjoined 
tendon  and  the  external  oblique,  it  will  lie  in  the  position  of 
the  inguinal  canal.  If  we  pass  the  finger  still  further  in,  we 
find  that  it  will  emerge  on  the  anterior  abdominal  wall  through 
the  EXTERNAL  RING — an  aperture  in  the  external  oblique 
situated  over  the  crest  of  the  pubes,  which  is  hidden  from  view 
by  the  conjoined  tendon  and  the  rectus,  and  which  therefore 
will  be  described  later.  To  complete  the  inguinal  canal,  the 
TRANSVERSALIS  FASCIA  must  be  in  position.  When  in  position, 
we  find  an  aperture  in  it,  situated  over  part  of  the  arch  already 
described,  J  inch  above  Poupart,  and  midway  between  the 
anterior  superior  spine  and  the  symphysis.  This  is  the 
INTERNAL  ABDOMINAL  RING,  and  through  it  the  cord  passes  to 
enter  the  inguinal  canal.  As  it  does  so,  it  receives  from  the 
transversalis  fascia  a  covering,  which  assists  in  supporting  and 
suspending  the  cord  in  the  canal.  To  this  covering  the  name 
of  INFUNDIBULIFORM  FASCIA  is  given.  It  is  simply  a  tubular 
projection  of  the  transversalis  fascia,  whose  mouth  is  the 
internal  ring.  Running  upwards  along  the  inner  border  of 
the  internal  ring  is  the  DEEP  EPIGASTRIC  ARTERY,  which  has 
arisen  from  the  external  iliac  (which  lies  directly  beneath  the 
ring),  and  is  running  upwards  and  inwards  to  pierce  the 
transversalis  fascia,  and  so  enter  the  sheath  of  the  rectus.  This 
artery  forms  the  outer  boundary  of  a  triangle,  formed  internally 
by  the  outer  border  of  the  rectus,  and  below  by  Poupart's  liga- 
ment. It  is  known  as  HESSELBACH'S  TRIANGLE.  When  a 
hernia,  instead  of  taking  the  ordinary  course  of  entering  the 
inguinal  canal  by  the  internal  ring  as  the  cord  does,  enters  it 


190  SURGICAL  ANATOMY 

through  some  portion  of  this  triangle,  it  is  called  a  DIRECT 
HERNIA,  in  distinction  to  the  ordinary  form  which  is  called 
OBLIQUE.  The  neck  of  a  direct  hernia  lies  to  the  inside  of  the 
deep  epigastric  artery,  whereas  that  of  an  oblique  lies  to  its 
outside.  Hesselbach's  triangle  is  divided  into  TWO  PORTIONS, 
an  outer  and  an  inner,  by  the  OBLITERATED  HYPOGASTRIC 
ARTERY,  which  runs  upwards  from  the  side  of  the  bladder  to 
the  umbilicus.  A  direct  hernia  may  pass  through  either  of 
these  divisions.  When  it  passes  through  the  portion  external 
to  the  obliterated  hypogastric,  it  is  called  an  external  direct 
inguinal  hernia,  and  pushes  before  it  a  covering  of  the  true 
transversalis  fascia,  instead  of  infundibuliform  fascia,  as  in 
the  case  of  an  oblique  hernia.  When  it  passes  through  the 
portion  internal  to  the  obliterated  hypogastric,  it  is  known  as 
an  internal  direct  inguinal  hernia,  and  pushes  before  it  not 
merely  a  process  of  transversalis  fascia,  but  also  either  per- 
forates or  pushes  before  it  a  layer  of  conjoined  tendon.  When 
the  peritoneum  is  in  position,  the  inguinal  region  presents  three 
jossce  when  viewed  from  behind  :  external,  external  to  the  deep 
epigastric  ;  middle,  between  deep  epigastric  and  obliterated 
hypogastric  ;  and  internal  (supravesical) ,  between  obliterated 
hypogastric  and  urachus.  We  may  next  trace  the  course  of  an 
oblique  inguinal  hernia  from  the  abdomen  to  the  scrotum,  see 
what  coverings  it  receives,  and  then  look  at  the  parts  concerned 
in  hernia  from  the  outside.  An  OBLIQUE  HERNIA  then  first 
pushes  before  it  a  layer  of  parietal  peritoneum  (and  extra- 
peritoneal  fat),  which  forms  the  proper  sac  of  the  hernia,  and 
then,  passing  through  the  internal  ring  alongside  the  cord, 
receives  a  covering  of  infundibuliform  fascia,  which  we  have 
already  seen  is  a  finger-like  projection  of  transversalis  fascia 
along  the  cord.  The  hernia  is  now  in  the  inguinal  canal,  with 
the  external  oblique  to  the  outside,  the  transversalis  fascia, 
and,  later,  the  conjoined  tendon  to  its  inner  side,  while 
Poupart's  ligament  is  below.  As  the  hernia  passes  down  the 
canal,  it  receives  a  covering  from  the  cremasteric  fascia  (partly 
cremaster  muscle,  partly  fascia),  and  then,  arrived  over  the 
crest  of  the  pubes,  it  emerges  from  the  canal  by  the  external 
ring  in  the  external  oblique  muscle,  receiving  as  it  does  so  a 
layer  of  intercolumnar  fascia.  Its  other  coverings  are  the 
superficial  fascia  and  skin.  If  now'the  abdominal  wall  be 
examined  from  the  front,  it  is  seen  that  the  external  oblique 


THE  ABDOMEN  191 

is  fused /vith  the  whole  length  of  Poupart's  ligament,  but  that 
there  is  an  aperture  in  its  insertion  into  the  crest  of  the  pubes — 
this  is  the  external  ring.  The  EXTERNAL  RING  is  bounded  by 
two  pillars,  formed  of  external  oblique  aponeurosis — an  ex- 
ternal, which  is  inserted  into  the  spine  of  the  pubes  ;  and  an 
internal,  which  is  inserted  into  the  symphysis  (some  fibres 
crossing  to  the  pubic  crest  of  the  opposite  side  form  the 
triangular  fascia).  These  two  pillars  are  bound  together 
above  by  the  inter  columnar  fascia,  which  consists  of  a  series  of 
arching  fibres  which  cross  from  one  pillar  to  the  other.  Thus 
the  NECK  OF  AN  INGUINAL  HERNIA  lies  inside  the  spine  of  the 
pubes  and  above  the  crest  of  the  pubes  and  Poupart's  liga- 
ment, whereas  the  NECK  OF  A  FEMORAL  HERNIA  lies  outside 
the  pubic  spine  and  below  Poupart's  ligament.  An  inguinal 
hernia  is  called  incomplete,  or  a  bubonocele,  when  it  does  not 
enter  the  scrotum,  and  is  spoken  of  as  complete,  or  scrotal, 
when  it  does.  In  the  female  it  enters  the  labium  when  com- 
plete, and  is  called  labial. 

As  the  anatomical  relationships  of  femoral  hernia  are 
closely  allied  to  those  of  inguinal,  it  will  be  well  to  study  these 
now,  although,  anatomically,  they  belong  to  the  thigh.  Looking 
once  more  at  the  internal  surface  of  the  abdominal  wall,  it  has 
been  seen  that  the  TRANSVERSALIS  FASCIA  forms  the  innermost 
covering — if  we  except  the  peritoneum  from  which  it  is 
separated  by  extraperitoneal  tissue— and  that  it  is  attached 
externally  to  the  inner  lip  of  the  iliac  crest  and  outer  half  of 
Poupart's  ligament,  while  internally  it  is  attached  to  the  ilio- 
pectineal  line  along  with  Gimbernat's  ligament.  Between 
these  attachments,  however,  the  fascia  turns  under  Poupart's 
ligament,  to  be  continued  into  the  tlrgri  as  the  ANTERIOR 

PORTION     Of     the     SHEATH     OF     THE     FEMORAL    VESSELS.       The 

POSTERIOR  PORTION  of  the  femoral  sheath  is  formed  by  the 
FASCIA  ILIACA,  which,  descending  in  front  of  the  iliacus 
muscle,  fuses  both  externally  and  internally  with  the  fascia 
transversalis  at  the  insertions  mentioned,  but  separates  from 
it  between  these  points  to  permit  of  the  passage  of  the  vessels 
which  it  accompanies  into  the  thigh.  Were  the  sheath  thus 
formed  just  of  sufficient  size  to  accommodate  the  vessels, 
the  possibility  of  femoral  hernia  occurring  would  be  slight. 
As  a  matter  of  fact,  however,  the  sheath  is  divided  into 
THREE  COMPARTMENTS,  the  outer  of  which  contains  the  artery, 


SURGICAL  ANATOMY 


18 


FIG.  22. — DIAGRAM  OF  ABDOMINAL  WALL  FROM  BEHIND. 


1.  External  oblique. 

2.  Internal  oblique. 

3.  Transversalis. 

4.  Rectus. 

5.  Conjoined   tendon,  with  indicator   to 

tip  of  external  ring. 

6.  Iliac  fascia  covering  iliacus  muscle. 

7.  Iliac   fascia   covering    anterior  crural 

nerve,    external   iliac   artery   to   its 
inner  side. 

8.  The  internal  ring,  an  opening  in  the 

fascia  transversal  is,  a  small  portion 
of  which  is  shown  in  white. 


9    Iliac    fascia   covering    psoas    muscle  ; 
external  iliac  vein  above  it. 

10.  Pectineus   muscle,    with   crural    canal 

above    it  (formed    by   transversalis 
and  iliac  fascia). 

11.  Gimbernat's  ligament. 

12.  Semilunar  fold  of  Douglas. 

13.  Deep  epigastric  artery. 

14.  Obliterated  hypogastric  artery. 

15.  Obturator  vessels. 

1 6.  P.ladder. 

17.  Urachus. 


THE  ABDOMEN  193 

the  middle  the  vein,  while  the  inner  forms  the  femoral  or 
crural  canal,  and  it  is  through  this  latter  inrrer  compartment 
that  the  femoral  hernia  makes  its  way  to  the  thigh.  As  it 
does  so,  it  pushes  before  it  parietal  peritoneum,  and  then  a 
covering  of  SEPTUM  CRURALE — a  layer  of  extraperitoneal 
tissue,  which  covers  the  ring,  or  mouth,  of  the  canal.  Its 
relations  here  are — Poupart's  ligament  above  and  in  front ; 
the  bone,  covered  by  pectineus  muscle  and  fascia  lata  below 
and  behind  ;  Gimbernat's  ligament  to  the  inside,  and  the 
femoral  vein  to  the  outside.  The  deep  epigastric  artery  lies 
just  above  and  outside  the  ring,  and  gives  off  a  small  pubic 
branch,  which  frequently  runs  down  along  the  inner  border 
of  the  crural  ring.  In  about.  3  per  cent,  of  cases  the 
OBTURATOR  ARTERY  from  the  external  iliac  is  absent,  and  then 
this  pubic  branch  of  the  deep  epigastric  enlarges  to  take  its 
place,  passing  round  the  inner  (and  sometimes  the  outer) 
border  of  the  ring  to  gain  the  obturator  foramen.  Were  it 
necessary  in  such  a  case  to  notch  Gimbernat's  ligament  for 
the  relief  of  a  strangulated  femoral  hernia,  this  abnormal 
vessel  might  be  cut,  and  several  cases  of  fatal  hemorrhage 
from  such  an  accident  have  been  recorded.  This  pubic  artery, 
or  aberrant  obturator  as  it  is  called  when  enlarged  in  the 
manner  described,  is  accompanied  by  the  pubic  vein  which 
communicates  between  the  obturator  and  external  iliac  veins. 
The  femoral,  or  crural  canal,  is  funnel-shaped,  and  only  extends 
about  J  inch  down  the  thigh,  terminating  under  the  saphenous 
opening  of  the  fascia  lata  of  the  thigh,  which  must  next  be 
described.  The  FASCIA  LATA  splits  at  its  upper  end  into  two 
portions,  an  outer,  or  iliac,  and  an  inner,  or  pubic,  which  over- 
lap one  another  to  form  the  oval  SAPHENOUS  OPENING.  The 
outer,  or  iliac,  portion  is  the  more  superficial,  lying  in  front  of 
the  femoral  sheath,  and  is  inserted  above  into  the  iliac  crest 
and  Poupart's  ligament.  The  inner  fibres  of  this  iliac  portion 
are  strongly  developed,  and  arch  upwards  and  inwards,  to  be 
inserted  into  the  inner  half  of  Poupart,  forming  what  is  known 
as  the  falciform  ligament,  while  their  free  concave  margin 
constitutes  the  superior  cornu  of  the  saphenous  opening.  If 
the  margin  of  this  superior  cornu  be  followed  downwards,  it 
is  seen  to  sweep  round  the  lower  margin  of  the  saphenous 
opening,  thus  forming  its  inferior  cornu,  and  then  to  run  up 
the  thigh  again  as  the  outer  margin  of  the  pubic  portion,  this 

13 


194  SURGICAL  ANATOMY 

time  extending  upwards  and  outwards  beneath  the  sheath  of 
the  vessels,  and  in  front  of  the  pectineus  and  adductor  longus, 
to  be  inserted  into  the  ilio-pectineal  line  along  the  insertion 
ot  Gimbernat's  ligament,  and  into  the  capsule  of  the  hip- 
joint.  The  saphenous  opening  thus  formed  is  covered  by  a 
special  thin  perforated  lamina,  which  is  known  as  the  cribriform 
fascia,  and  which  is  perforated  by  the  internal  saphenous  vein, 
which  dips  in  here  to  join  the  femoral  vein.  A  femoral  hernia, 
then,  on  reaching  the  lower  extremity  of  the  short  femoral 
canal,  turns  forwards,  carrying  a  covering  of  cribriform  fascia 
before  it  as  it  does  so,  and  presents  under  the  skin  and  super- 
ficial fascia.  A  curious  point  is  that,  as  femoral  herniae  come 
forward,  they  also  tend  to  turn  upwards  over  Poupart's  liga- 
ment, thus  making  MISTAKES  IN  DIAGNOSIS  between  femoral 
and  inguinal  herniae  possible.  Of  course,  the  neck  of  a  femoral 
hernia  is  below  Poupart,  and  external  to  the  spine  of  the  pubes. 
Various  reasons  have  been  adduced  to  explain  this  upward 
tendency.  The  unyielding  character  of  the  saphenous  cornua 
and  the  traction  upon  the  mesentery  are  probable  causes. 
The  femoral  canal  is  rendered  most  lax  when  the  thigh  is  flexed, 
adducted,  and  rotated  inwards,  a  point  to  remember  in 
applying  TAXIS,  when  it  should  also  be  recollected  that  the 
sharp  unyielding  edge  of  Gimbernat's  ligament  is  frequently 
the  constricting  cause,  and  may  wound  the  bowel  if  undue 
force  is  exercised.  Both  bladder  and  ovary  form  occasionally 
the  contents  of  femoral  herniae. 

A  less  common  form  of  hernia  is  the  OBTURATOR,  in  which 
the  bowel,  pushing  the  parietal  peritoneum,  extraperitoneal  fat, 
and  pelvic  fascia  before  it,  passes  downwards,  forwards,  and 
inwards  through  the  obturator  canal,  where  it  may  remain  under 
the  obturator  externus,  or,  perforating  or  going  to  one  side 
of  this  muscle,  may  present  under  the  pectineus,  behind  and 
to  the  inner  side  of  the  femoral  vessels,  and  about  a  finger- 
breadth  beneath  the  position  of  exit  of  a  femoral  hernia.  The 
obturator  vessels  and  nerve  are  generally  to  the  outer  side 
of  the  sac,  and  pressure  on  the  nerve  may  occasion  pain  on  the 
inner  side  of  the  thigh,  and  on  moving  the  hip-joint.  This 
form  of  hernia  occurs  most  frequently  in  females,  and  while 
it  generally  consists  of  bowel,  may  contain  bladder  or  ovary. 
The  hernia  is  generally  small,  and  may  produce  no  external 
swelling  even  when  strangulated.  In  such  cases  pain  on 


THE  ABDOMEN  195 

the  inner  side  of  the  femoral  vessels  and  inner  aspect  of  the 
thigh  Inay  assist  the  diagnosis,  while  the  inner  aspect  of  the 
canal  may  be  examined  per  vaginam  in  the  female,  or  per 
rectum  in  the  male,  and  the  hernia  possibly  even  reduced  in  this 
manner.  In  operating  for  obturator  hernia  a  vertical  incision 
is  made  midway  between  the  femoral  vein  and  pubic  spine, 
the  fascia  lata  divided,  and  the  interval  between  the  pectineus 
and  adductor  longus  denned.  The  muscles  are  separated, 
the  pectineus  being  partially  divided  if  necessary  with  great 
care,  and  the  hernia  exposed  and  treated.  Cutting  to  relieve 
strangulation  must  always  be  done  with  care,  as  the  relation 
of  the  vessels  to  the  sac  varies. 

In  order  to  more  fully  explain  certain  forms  of  inguinal 
hernia,  and  as  an  introduction  to  the  study  of  the  abdominal 
cavity,  it  is  necessary  to  turn  shortly  to  the  relationship  of 
the  peritoneum  to  the  abdominal  viscera,  and  to  the  descent 
of  the  testicle.  The  PERITONEUM,  then,  is  a  shut  sac,  which 
has  no  contents,  but  whose  walls  are  capable  of  great  invagina- 
tion.  We  may  imagine  this  closed  sac  (or  balloon)  placed  in 
the  abdominal  cavity,  after  which  the  viscera  to  obtain  room 
would  require  to  push  the  sac  wall  before  them,  and  in  so  doing 
would  receive  a  covering  from  it.  Thus,  a  loop  of  bowel 
projects  itself  into  this  hollow  sac,  and  in  so  doing  receives  a 
covering  of  peritoneum — its  serous  layer — while  the  track  of 
its  projection  is  lined  by  a  double  layer  of  peritoneum— the 
mesentery — in  which  the  vessels  to  supply  the  bowel  with 
blood,  etc.,  run.  Unfortunately,  however,  the  covering  of 
peritoneum  which  the  invaginating  portion  of  bowel  receives 
is  not  taken  into  account  when  speaking  of  various  peritoneal 
layers,  but  is  simply  spoken  of  as  the  serous  coat  of  the  bowel 
itself.  Thus,  to  get  at  the  bowel  through  an  abdominal 
incision,  we  only  cut  the  parietal  peritoneum;  the  various 
loops  of  bowel  then  present,  but  each  is  covered  by  its  serous 
layer  of  peritoneum,  which  we  neglect  to  regard  as  such.  The 
testicle  in  the  foetus  is  an  abdominal  organ,  situated  at  the  lower 
end  of  the  kidney.  Thus,  like  the  other  viscera,  it  is  outside 
the  peritoneum,  and,  like  the  kidney,  it  is  only  partially 
covered  by  it.  The  testicle  gradually  descends  from  this 
position  (pulled,  it  is  supposed,  by  a  foetal  structure  called  the 
gubernaculum) ,  until  at  birth  it  occupies  the  scrotum,  having 
descended  through  the  inguinal  canal.  In  its  descent  it  drags 

13—2 


96 


SURGICAL  ANATOMY 


out  a  finger-like  process  of  peritoneum  with  it  (this,  then,  is 
an  evagination,  and  not  an  invagination) ,  which  forms  an 
open  peritoneal  canal  running  through  the  inguinal  canal, 


C4 


FIG.  23.— DIAGRAM  ILLUSTRATING  THE  DEVELOPMENTAL  OBLITERATION  OF 
THE  FUNICULAR  PROCESS  (SERIES  A),  AND  THE  FORMS  OF  INGUINAL 
HERNIA  (SERIES  B),  AND  HYDROCELE  (SERIES  C)  WHICH  MAY  ARISE 

THEREFROM. 

SERIES  A. — NORMAL  DESCENT  OF  TESTICLE. 

1.  Funicular  process  entirely  open  (congenital). 

2.  Funicular  process  closed  by  septum  at  internal  ring,  and  partially  so  at 

junction  with  tunica  vaginalis  (infantile). 

3.  Funicular  process  closed  both  above  and  below  (infantile). 

4.  Funicular  process  entirely  obliterated  (adult). 

SERIES  B. — DRVELOPMENTAL  VARIETIES  OF  INGUINAL  HERNIA. 

1.  Congenital  (one  layer  of  peritoneum  to  cut  through). 

2.  Infantile  (encysted)  (two  layers  of  peritoneum  to  divide). 

3.  Infantile  (possibly  three  layers  of  peritoneum  to  divide  ;  testicle  in  front). 

4.  Adult  (one  layer  of  peritoneum  to  divide). 

SERIES  C.— DEVELOPMENTAL  VARIETIES  OF  HYDROCKLK. 

1.  Congenital. 

2.  Infantile— bilocular  ;  scrotal,  and  intra-pelvic. 

3.  Infantile — encysted  of  cord. 

4.  Adult  of  tunica  vaginalis. 


called  the  FUNICULAR,  OR  VAGINAL,  PROCESS,  the  inner  end  of 
which  opens  into  the  general  peritoneal  cavity,  while  the 
outer  expanded  end  is  closed,  and  partially  invests  the  testicle. 


THE  ABDOMEN  197 

This^s  the  condition  of  affairs  at  birth,  and  a  hernia  may  come 
down  through  this  patent  peritoneal  canal  into  the  scrotum. 
This  would  constitute  a  CONGENITAL  HERNIA,  the  bowel 
(covered  by  its  serous  coat)  would  be  in  contact  with  the 
testicle  (covered  by  its  serous  coat),  and  there  would  only  be 
one  layer  of  peritoneum  between  it  and  the  outer  coverings. 
Similarly  the  lower  portion  of  this  canal  may  distend  with 
serous  fluid,  which  may  reach  it  from  the  abdominal  cavity, 
with  which  it  freely  communicates,  and  form  a  CONGENITAL 
HYDROCELE.  Soon  after  birth,  in  a  normal  case,  this  patent 
funicular  process  becomes  obliterated,  leaving  the  lower  end, 
however,  to  form  the  TUNICA  VAGINALIS  of  the  testicle,  which 
thus  becomes  entirely  separated  from  the  peritoneum.  The 
obliteration  of  the  funicular  process  commences  usually  at 
the  internal  ring,  and  a  little  later  just  above  the  epididymis, 
septa  forming  at  these  points.  If  the  intervening  portion  of 
the  process  becomes  distended  with  fluid,  an  (infantile) 
ENCYSTED  HYDROCELE  OF  THE  CORD  is  formed.  On  the  other 
hand,  bowel  may  enter  the  unobliterated  portion  from  the 
abdomen,  pushing  the  upper  septum  before  it.  Such  a  form 
of  hernia  is  called  an  ENCYSTED  INFANTILE  HERNIA.  In  it 
the  bowel  is  quite  separate  from  the  testicle,  and  is  enclosed 
by  two  peritoneal  layers  (counting  the  stretched  septum  as 
one,  but  not  reckoning  the  serous  coat  of  the  bowel).  Again, 
a  hydrocele  may  form  in  the  common  funicular  process  and 
tunica  vaginalis,  and  push  the  septum  at  the  neck  of  the 
process  before  it  into  the  abdomen,  forming  an  infantile 
bilocular  hydrocele.  In  another  form  of  INFANTILE  HERNIA 
the  bowel  does  not  come  down  into  the  funicular  process,  but 
comes  down  behind  it,  pushing  a  layer  of  parietal  peritoneum 
before  it  as  it  does  so,  or  taking  advantage  of  a  peritoneal 
diverticulum,  which  Lockwood  states  occurs  in  that  position 
from  the  action  of  the  gubernaculum .  Here,  also,  the  bowel 
is  quite  apart  from  the  testicle,  and  in  operating  from  the 
front  three  layers  of  peritoneum  require  to  be  cut  through 
before  the  serous  coat  of  the  bowel  is  reached.  Although  these 
forms  of  hernia  and  hydrocele  are  called  congenital  and 
infantile,  they  do  not  necessarily  occur  at  birth  or  in  infancy, 
but  may  occur  in  after  life.  Sometimes  the  testicle  does  not 
descend  into  the  scrotum  until  some  years  after  birth,  but  the 
funicular  process  may  do  so  notwithstanding,  and  along  it  a 


198  SURGICAL  ANATOMY 

congenital  hernia  may  descend.  The  inguinal  canal  in  the 
foetus  is  relatively  shorter  than  in  the  adult,  while  in  the  female 
it  is  rather  longer  but  narrower  than  in  the  male. 

In  the  female  the  canal  is  occupied  by  the  round  ligament, 
along  which  a  process  of  peritoneum,  called  the  CANAL  OF 
NUCK,  descends  in  the  foetus  for'  a  short  distance.  A  con- 
genital form  of  inguinal  hernia  in  the  female  may  occur  into 
this  sac.  It  should  be  remembered  that  inguinal  hernia  is 
by  no  means  uncommon  in  women,  and  that  femoral  hernia 
is  frequently  met  with  in  men,  although,  as  a  rule,  perhaps 
inguinal  hernia  is  more  common  in  men  and  femoral  in  women. 
Where  a  hernia  is  STRANGULATED  by  some  constricting  band 
about  the  inner  opening  of  the  peritoneal  sac,  it  is  frequently 
necessary  to  make  a  slight  cut  in  the  band  in  order  to  relieve 
the  constriction.  In  the  case  of  inguinal  hernia,  the  blade  of 
the  knife  should  generally  be  directed  upwards  and  outwards 
so  as  to  avoid  the  deep  epigastric  artery,  while  in  femoral 
hernia  it  should  be  directed  upwards  and  inwards  so  as  to 
keep  clear  of  the  femoral  vein,  and  in  acquired  umbilical 
hernia  directly  upwards. 

A  RICHTER'S  HERNIA  is  one  in  which  only  a  portion  of  the 
circumference  of  the  bowel  is  in  the  sac.  Some  apply  the  term 
Littre's  hernia  to  the  same  condition,  or  to  a  hernia  of  a  small 
knuckle  of  bowel,  or  of  a  diver ticulum. 

With  regard  to  the  OPERATIVE  TREATMENT  OF  INGUINAL 
HERNIA,  many  methods  of  dealing  with  the  sac  and  of  closing 
the  inguinal  canal  have  been  devised.  In  children  simple 
ligature  of  the  sac  as  far  up  as  possible  has  been  found  to  yield 
good  results.  In  adults  the  sac  is  variously  removed,  drawn 
to  some  abnormal  position,  or  placed  as  a  pad  on  the  inner 
surface  of  the  abdominal  wall,  with  the  object  of  obliterating 
the  funnel-shaped  orifice  of  the  canal,  which  may  be  said  to 
'  tempt'  the  hernia  (Macewen).  With  the  object  of  further 
removing  '  temptation,'  redundant  omentum  is  generally 
removed,  as  omentum  frequently  opens  out  the  path  for  bowel 
to  follow.  In  this  connection  also  it  may  be  said  that  abnormal 
length  of  mesentery  is  generally  looked  upon  as  a  predisposing 
cause  of  hernia.  The  closure  of  the  canal  is  generally  accom- 
plished by  drawing  the  arching  conjoined  tendon  down  behind 
Poupart's  ligament,  and  stitching  up  the  external  ring  (Mac- 
ewen), which  latter  in  many  operations  is  first  slit  up  to  give 


THE  ABDOMEN^  199 

easier  Access  to  the  conjoined  tendon  (Bassini).  The  cord  is 
variously  treated,  being  left  at  the  inner  side  of  the  portion  of 
conjoined  tendon  which  has  been  pulled  down  (in  which  case  it 
occupies  a  small  natural  channel,  which  cannot  be  obliterated 
owing  to  the  vertical  direction  of  the  conjoined  fibres  at  that 
point,  and  so  is  relieved  from  pressure)  (Macewen),  or  brought 
out  at  the  position  of  the  internal  ring,  and  then  passed  between 
the  stitched  conjoined,  and  external  oblique  (Bassini),  or 
even  taken  out  to  the  anterior  superior  spine  by  others 
(Halsted). 

In  FEMORAL  HERNIA  there  is  less  tendency  to  recurrence 
if  care  be  taken  to  invaginate  or  otherwise  treat  the  sac  so  as 
to  remove  its  gaping  mouth.  Some  have  tried  to  obliterate 
the  canal  by  turning  up  a  flap  of  pectineus  and  its  fascia  over 
the  mouth  of  the  canal,  and  attaching  it  above  to  Poupart's 
ligament  (Cheyne),  while  others  seek  to  do  so  by  suturing  the 
tense  ligament  down  to  the  subjacent  bone. 

Before  leaving  the  subject  of  hernia  some  of  the  rarer  forms 
may  be  mentioned.  In  pudendal  hernia  the  bowel  descends 
between  the  ascending  ramus  of  the  ischium  and  the  vagina  to 
the  posterior  portion  of  the  labium.  In  perineal  hernia  it 
perforates  the  anterior  fibres  of  the  levator  ani,  and  appears 
between  the  prostate  and  rectum,  carrying  the  recto-vesical  (and 
anal)  fasciae  before  it.  A  sciatic  hernia  passes  through  the  great 
sacro-sciatic  notch,  and  appears  under  the  gluteus  maximus. 
A  lumbar  hernia  presents  through  the  triangle  of  Petit  between 
the  latissimus  dorsi  and  external  oblique,  just  above  the 
highest  point  of  the  iliac  crest,  and  in  front  of  the  quadratus 
lumborum,  and  either  carries  before  it  or  perforates  the  fascia 
lumborum  and  internal  oblique.  Diaphragmatic  hernia  is 
most  usually  congenital,  occurring  through  some  develop- 
mental defect,  and  is  more  common  on  the  left  side  owing 
to  the  presence  of  the  liver  on  the  right,  passing  through 
connective  tissue  intervals  between  sternal  and  costal  origins 
of  the  diaphragm  in  front  ;  or  vertebral  and  costal  origins 
behind  ;  or  the  cesophageal  foramen.  It  does  not  invade  the 
aortic  or  vena  caval  foramina.  The  stomach,  or  transverse 
colon,  forms  the  most  common  contents  of  the  protrusion. 


200  SURGICAL  ANATOMY 

THE  ABDOMINAL  CAVITY. 

The  peritoneum  is  a  single  closed  serous  sac,  composed  of  a 
thin  fibrous  layer,  lined  on  its  inner  surface  with  endothelium. 
This  closed  sac  is  divided  into  two  portions — a  greater  sac  and 
a  lesser  sac — by  a  constricted  neck  (called  the  foramen  of 
Winslow),  through  which  the  two  portions  communicate. 
This  neck  is  twisted,  so  that  the  small  sac  lies  behind  the  great 
sac ;  and  below  the  level  of  the  stomach,  which  separates  them, 
the  great  sac  is  invaginated  by  a  process  of  the  small  sac,  the 
two  together  (invaginated  and  invaginating)  forming  the 
great  omentum.  This  sac  has  no  contents,  the  various  surfaces 
being  practically  in  contact,  save  for  a  little  serous  fluid  which 
lubricates  them,  and  renders  the  free  movements  of  the 
viscera  possible.  The  GREATER  SAC  lines  the  greater  part  of 
the  abdominal  cavity.  That  portion  lining  the  anterior 
abdominal  wall  is  comparatively  smooth  and  free  from  inter- 
ruption, whereas  that  lining  the  posterior  abdominal  wall  is 
thrown  into  folds  by  the  various  viscera  which,  carrying  it 
before  them,  project  into  and  completely  fill  the  abdominal 
cavity,  and  thus,  so  to  speak,  obliterate  the  cavity  of  the 
peritoneal  sac.  The  ABDOMINAL  VISCERA  are  either  fixed 
directly  by  connective  tissue  to  the  posterior  abdominal  wall, 
or  are  suspended  from  it  by  bloodvessels.  Where  viscera  are 
FIXED  DIRECTLY  to  the  posterior  abdominal  wall,  the  peri- 
toneum is  generally  pushed  before  or  invaginated  by  them, 
the  reflections  of  the  peritoneum  from  the  abdominal  wall  to 
a  viscus  being  frequently  termed  ligaments.  The  organs  vary 
very  much  in  the  extent  to  which  they  are  covered  by  peri- 
toneum, the  spleen  having  a  very  complete  coat,  while  the 
kidney  and  pancreas  have  only  partial  coats,  it  being  possible, 
therefore,  for  abscesses  in  connection  with  these  latter  organs 
to  discharge  externally  without  involving  the  peritoneal 
cavity.  In  this  connection  it  is  interesting  to  note  that  while 
the  interior  of  the  peritoneal  cavity  is  very  prone  to  microbic 
infection,  the  exterior  is  very  resistant,  and  this  holds  true 
even  of  the  serous  peritoneal  coat  of  bowel,  etc.  Thus,  a 
large  pelvic  abscess  may  fail  to  cause  peritonitis,  and  a  per- 
forating ulcer  of  the  appendix  may  find  its  progress  stopped  by 
the  thin  serous  layer.  As  an  example  of  the  SUSPENDED  TYPE 
of  viscus  the  bowel  may  be  taken.  It  is  projected  into  the 


THE  ABDOMEN  201 

abdomUial  cavity,  invaginating  the  posterior  layer  of  the 
peritoneal  sac,  and  carrying  a  visceral  layer  of  peritoneum 
before  it,  which  is  then  considered  as  the  serous  coat  of  that 
viscus,  and  is  no  longer  spoken  of  as  the  peritoneum.  Covering 
over  the  various  branches  of  the  bloodvessels,  which,  arising 
from  the  aorta,  run  forwards  to  supply  the  bowel,  is  a 
double  layer  of  invaginated  peritoneum,  which  is  called  the 
MESENTERY.  Thus  it  will  be  understood  that  all  viscera  lie 
outside  the  cavity  of  the  peritoneum,  which  forms  a  covering 
for  all  the  viscera  which  are  projected  into  it.  There  is  one 
exception  to  the  statement  that  the  peritoneum  is  a  closed 
sac — the  Fallopian  tubes  open  into  it. 

The  FORAMEN  OF  WINSLOW,  through  which  the  greater  sac 
communicates  with  the  less,  is  situated  below  and  behind  the 
portal  fissure  of  the  liver,  while  the  first  part  of  the  duodenum 
and  hepatic  artery  lie  below  it.  Owing  to  a  twist  at  the  foramen 
of  Winslow,  the  SMALL  SAC  is  situated  behind  the  large  one,  and 
occupies  the  space  between  the  posterior  wall  of  the  stomach  and 
the  posterior  abdominal  wall.  Above  this  point  it  extends  up- 
wards between  the  liver  and  abdominal  wall,  but  while  crossing 
from  the  upper  border  of  the  stomach  to  the  under  surface  of 
the  liver  its  anterior  wall  comes  in  contact  with  the  posterior 
wall  of  the  great  sac  (which  comes  up  over  the  anterior  surface 
of  the  stomach  to  extend  to  the  liver),  and  these  two  layers 
together  are  called  the  LESSER  OMENTUM  (GASTRO-HEPATIC 
OMENTUM)  .  Below  the  stomach  the  lesser  sac  invaginates  the 
greater  sac,  and  thus  we  have  extending  from  the  lower 
border  or  greater  curvature  of  the  stomach  a  double  layer  of 
peritoneum,  the  descending  portion  being  composed  of  an 
anterior  layer  of  great  sac  and  a  posterior  of  lesser  sac.  This 
double  layer  extends  down  a  variable  distance  in  front  of  the 
other  viscera,  and  then,  turning  on  itself,  runs  up  again,  the 
ascending  and  descending  layers  being  in  close  contact  with 
one  another.  When  the  two  ascending  layers  meet  the  trans- 
verse colon,  they  split  to  enclose  it,  but  again  unite  to  form 
what  is  called  the  TRANSVERSE  MESOCOLON.  The  long 
process,  composed  of  layers  of  both  sacs,  is  called  the  GREAT 
OMENTUM  (gastrocolic) .  It  forms  an  apron  in  front  of  the 
small  intestine  of  very  variable  length,  is  generally  loaded  with 
fat,  and  is  of  considerable  importance  surgically.  Thus,  a 
very  long  omentum  is  generally  considered  a  predisposing,  if 


202 


SURGICAL  ANATOMY 


not  actual,  cause  of  hernia,  as  it  is  frequently  found  to  precede 
the  appearance  of  the  bowel,  not  infrequently  forming  an 
omental  sac  over  the  bowel,  which  may  thus  be  said  to  be 
'  encouraged  '  by  the  omen  turn  forming  a  path  for  it.  Some- 
times also  a  hernial  protrusion  contains  only  omentum,  no 
bowel  being  present  (epiplocele) .  Lockwood  states  that  under 
the  age  of  forty-five  the  omentum  can  rarely  be  drawn  down 
below  the  pubic  spine,  whereas  in  later  years  it  can  be.  Venous 


FIG.  24. —  DIAGRAM  OF  PERITONEUM,  ITS  SACS  AND  FOLDS. 

Lesser  sac  is  shaded.  Arrow  through  foramen  of  Wins  low.  Note  how  transverse  colon 
with  its  mesocolon  forms  a  diaphragm  dividing  the  abdominal  cavity  into  supra-  and  infra- 
mesocolic  compartments,  the  stomach  occupying  the  former  and  the  small  intestine  the 
latter. 

congestion  frequently  produces  great  increase  in  the  size  of  a 
herniated  omental  mass,  and  the  same  cause  occasionally  pro- 
duces a  varicose  condition  of  its  veins,  the  mass  therefore  simu- 
lating varicocele.  On  the  other  hand,  omentum  has  a  very 
definite  effect  upon  inflammatory  affections  of  the  abdominal 
cavity.  In  many  cases  it  takes  a  large  share  in  walling  off 
suppurative  processes,  and  thus  protecting  the  general  peri- 
toneal surface  from  infection.  In  some  cases  the  extremity 


THE  ABDOMEN  203 

of  the  orrientum  may  become  adherent  to  some  of  the  pelvic 
organs,  and  subsequently,  owing  to  movements  of  the 
intestine,  may  become  twisted  into  a  rather  tense  cord,  under 
which  a  loop  of  bowel  may  become  strangulated.  Bowel  may 
also  become  strangulated  by  passing  through  an  aperture  in 
the  mesentery  or  omentum.  Where  any  structure  becomes 
adherent  to  the  omentum,  it  may  derive  a  large  proportion 
of  its  blood-supply  from  it.  This  may  occur  in  the  case  of  the 
sac  of  an  omental  hernia  ;  in  ovarian  tumour,  with  twisted 
pedicle,  etc.  In  abdominal  wounds  the  omentum  may  pro- 
trude, block  up  the  opening,  and  so  prevent  the  escape  of 
blood. 

It  has  been  stated  above  that  the  stomach  is  interposed 
between  the  two  sacs,  the  great  sac  lying  in  front  and 
the  smaller  behind.  This  relationship  of  the  posterior  wall 
of  the  stomach  to  the  lesser  sac  is  a  point  of  much  surgical 
importance,  as,  when  a  gastric  ulcer  ruptures  on  the  posterior 
wall,  it  opens  into  the  lesser  sac,  and  the  escaping  contents 
are  much  circumscribed,  adhesions  generally  forming  rapidly, 
which  limit  the  process  ;  whereas,  when  the  rupture  occurs  on 
the  anterior  wall  the  large  anterior  sac  and  contained  viscera 
are  very  apt  to  be  affected,  adhesions  occurring  here  much 
less  readily. 

The  STOMACH  lies  in  the  supramesocolic  compart- 
ment of  the  abdomen,  almost  entirely  to  the  left  of  the 
middle  line,  occupying  a  space  immediately  under  the  left 
dome  of  the  diaphragm  and  left  lobe  of  the  liver,  and  extending 
down  into  the  epigastric  region.  The  space  which  it  occupies, 
and  to  a  less  extent  its  relations,  vary  greatly  according  to  its 
state  of  distension.  The.CARDiA,  or  junction  between  the 
oesophagus  and  the  stomach,  is  the  most  fixed  point,  and  is 
situated  deeply,  about  4  inches  behind  and  i  inch  outside  the 
junction  of  the  seventh  left  costal  cartilage  with  the  sternum, 
about  the  level  of  the  eleventh  dorsal  vertebra.  From  this 
point  the  LESSER  CURVATURE,  or  upper  and  right  border, 
curves  round  the  spine  downwards,  forwards,  and  to  the  right 
to  the  pylorus,  giving  attachment  above  to  the  lesser,  or  gastro- 
hepatic,  omentum.  The  GREATER  CURVATURE  is  at  first  directed 
backwards  and  upwards,  forming  an  angle  with  the  cardia, 
and  then  sweeps  round,  to  run  from  left  to  right,  and  slightly 
forwards  and  downwards,  and  finally  it  runs  up  to  the  pylorus. 


204 


SURGICAL  ANATOMY 


It  gives  attachment  to  the  great  omentum,  and  on  the  left  to 
the  gastro-splenic  omentum.  The  level  of  the  greater  curvature 
varies  greatly,  according  to  the  amount  of  distension,  and  it 
carries  with  it  the  transverse  colon,  which  lies  in  close  relation- 
ship to  it.  When  not  distended,  it  generally  corresponds  to  a 


FIG.  25.  —  THE  SUPRAMESOCOLIC  COMPARTMENT  OF  THE  ABDOMEN. 
PORTIONS  OF  STOMACH  AND  LIVER  HAVE  BEEN  REMOVED  TO  DISPLAY 
THE  DIAPHRAGM  FORMED  BY  THE  TRANSVERSE  COLON  AND  MESO- 
COLON  WITH  KIDNEY,  SPLEEN,  AND  PANCREAS. 


1.  Aorta. 

2.  (Esophagus. 

3.  Stomach. 

4.  Diaphragm. 

5.  Pylorus. 

6    Right  lobe  of  liver. 


7.  Gall-bladder. 

8.  Transverse  colon. 

9.  Suprarenal. 
10.  Kidney. 
u.  Pancreas. 
12.  Spleen. 


13.  Transverse  mespcolon  (form- 

ing shelf  or  diaphragm). 

14.  Splenic  flexure. 

15.  Hepatic  flexure. 

16.  Duodeno-jejunal  junction. 

17.  Descending  aorta. 


horizontal  line,  joining  the  tips  of  the  tenth  costal  cartilages. 
This  greater  curvature  sometimes  presents  a  DISTINCT  NOTCH, 
which  indicates  the  division  between  the  body  of  the  stomach 
and  the  pyloric  portion.  The  expanded  portion  of  the  stomach 
which  lies  to  the  left  of  the  cardia  is  called  the  FUNDUS,  and 
its  highest  point  lies  beneath  the  diaphragm  just  above  and 


THE  ABDOMEN  205 

inside  the  apex  of  the  heart.  The  portion  lying  between 
fundus  and  pylorus  is  called  the  BODY.  The  PYLORIC  END 
of  the  stomach  is  more  movable  than  the  cardiac,  and  varies 
in  position,  according  to  the  amount  of  distension  of  the 
stomach.  Generally  it  lies  about  J  inch  to  the  right  side  of  the 
mid-point  between  the  suprasternal  notch  and  symphysis, 
or  2|  inches  above  the  umbilicus,  being  situated  below  and 
anterior  to  the  cardia.  It  is  described  as  consisting  of  a 
wider  antrum,  or  vestibule,  to  the  left,  and  canal  on  the  right, 
leading  up  to  the  valve.  The  pyloric  valve  is  marked  on  the 
surface  by  a  slight  constriction,  is  directed  from  before  back- 
wards, and  lies  upon  the  neck  of  the  pancreas  with  the  liver 
above  it,  and  the  gall-bladder  on  its  right. 

The  stomach  may  be  said  to  occupy  a  wedge-shaped  space 
(supramesocolic  compartment  of  the  abdomen),  with  rounded 
angles  at  the  base ;  the  apex,  situated  on  the  right  side,  being 
formed  by  the  junction  of  the  liver  and  the  transverse  colon. 
Above,  from  left  to  right,  are  the  diaphragmatic  dome,  and 
then  the  left  lobe  of  the  liver  sloping  down  to  the  right  to  meet 
the  colon.  Below  lie  the  spleen  behind  and  to  the  left,  and 
more  to  the  front  the  upper  surface  of  the  pancreas,  while  the 
left  suprarenal  and  kidney  fill  a  slight  interval  between  the  two 
posteriorly.  In  front  of  the  pancreas  are  the  transverse  meso- 
colon  and  transverse  colon.  Thus  a  FLOOR  is  formed  for  the 
stomach  of  spleen,  kidney,  and  pancreas  behind,  with  trans- 
verse mesocolon  and  colon  in  front,  these  latter  structures 
foiming  almost  a  DIAPHRAGM,  separating  the  stomach  above 
in  the  supramesocolic  compartment  from  the  underlying  small 
intestine  in  the  submesocolic  compartment.  The  base  of  the 
wedge,  situated  on  the  left  side,  is  formed  by  the  spleen  and 
the  diaphragm.  This  space  is  closed  in,  in  front,  by  the 
diaphragm,  the  fifth  to  the  eighth  ribs  and  the  costal  cartilages, 
and  a  portion  of  the  anterior  abdominal  wall  and  of  the  liver. 

The  whole  BLOOD-SUPPLY  of  the  stomach,  which  is  very 
abundant,  is  derived  directly  or  indirectly  from  the  cceliac  axis. 
The  coronary  artery  arises  from  it  directly,  and  runs  along  the 
lesser  curvature  to  join  the  pyloric  branch  of  the  hepatic. 
The  arch  thus  formed  gives  off  several  large  branches.  On 
the  greater  curvature  an  arch  is  formed  by  the  gastroduodenal 
of  the  hepatic  giving  off  the  right,  and  the  splenic  giving  off 
the  left  gastro-epiploic  arteries,  which  vessels  freely  anasto- 


206  SURGICAL  ANATOMY 

mose,  and,  in  addition  to  the  vasa  brevia  from  the  splenic, 
supply  branches  to  the  stomach  wall.  The  coronary  and  the 
pyloric  vein  join  the  portal  trunk ;  the  right  gastro-epiploic 
joins  the  superior  mesenteric,  the  left  the  splenic,  along  with 
the  vasa  brevia  veins. 

The  LYMPHATICS  run  to  the  superior  and  inferior  gastric 
glands,  situated  along  the  lesser  and  greater  curves  respectively, 
and  the  splenic,  and  finally  join  the  coeliac  glands. 

The  NERVE-SUPPLY  is  from  the  pneumogastrics,  the  left 
lying  on  the  front,  and  the  right  on  the  posterior  surface 
of  the  oesophagus,  and  then  reaching  the  upper  and  lower 
stomach  surfaces  respectively,  which  they  supply  after 
joining  with  the  sympathetic  fibres  of  the  cceliac  plexus. 
The  sympathetic  nerves  are  associated  with  the  seventh  and 
eighth  spinal  segments,  and  thus  in  stomach  diseases  the 
skin  supplied  by  these  segments  may  become  tender  or  even 
painful,  pain  being  complained  of  below  the  angle  of  the 
scapula. 

Not  infrequently  the  stomach  may  be  found  to  be  abnor- 
mally contracted  or  dilated.  CONTRACTION  is  generally  met 
with  in  cases  of  stricture  of  the  oesophagus,  where  it  may 
occur  to  such  an  extent  as  to  render  certain  operations  almost 
impossible.  Also  on  account  of  its  small  size,  and  the  fact 
that  the  transverse  colon  frequently  ascends  in  front  of  it,  it 
may  be  difficult  to  find  after  the  abdomen  has  been  opened. 
In  such  cases  it  is  advisable  to  run  the  finger  upwards  and 
•backwards  until  the  under  surface  of  the  liver  is  reached,  and 
then  push  forwards  the  structure  in  front  of  it.  In  cases  of 
contraction  the  pylorus  generally  lies  almost  in  the  middle 
line.  When  the  stomach  DILATES,  the  fundus  pushes  the 
diaphragm  upwards,  and  thus  sometimes  causes  faintness  in 
flatulent  distension  from  actual  pressure  on  the  heart.  The 
body  of  the  stomach  also  ascends  while  the  greater  curvature 
comes  forwards,  displacing  the  colon  and  small  intestines 
downwards.  The  pyloric  segment  is  displaced  further  to  the 
right,  and  becomes  markedly  curved.  Acute  or  chronic 
dilatation  may  arise  from  a  variety  of  causes,  such  as  pyloric 
obstruction  (stenotic  gastrectasis)  and  atony  of  the  muscular 
coats  (atonic  gastrectasis),  etc.  As  a  rule,  there  is  first  a 
period  of  muscular  hypertrophy,  but  this  is  generally  followed 
by  atrophy,  after  which  the  stomach  may  become  very  large, 


THE  ABDOMEN  207 

pressing  upwards  on  heart  and  lungs,  causing  palpitation  and 
dyspncei,  while  below  it  may  reach  almost,  if  not  quite,  to 
the  pubis  (ptosis).  The  pylorus  also  becomes  dragged  down, 
so  as  to  be  palpable  in  some  cases  through  the  abdominal  wall. 

The  stomach  is  frequently  affected  by  ULCERS,  which  occur 
most  often  on  the  posterior  wall  toward  the  lesser  curvature, 
but  may  occur  at  any  part,  and  \vhich  also  very  frequently 
affect  the  pylorus  and  duodenum.  Such  ulcers  may  be 
chronic,  and  beyond  causing  occasional  haemorrhage  by 
involving  some  of  the  larger  vessels  in  the  mucous  or  sub- 
mucous  coats,  may  not  call  for  surgical  interference.  In 
healing  they  frequently  cause  considerable  contraction,  which, 
when  situated  in  the  body  of  the  stomach,  may  give  rise  to 
an  hour-glass  deformity,  or,  when  situated  over  the  pylorus, 
may  cause  pyloric  obstruction.  In  other  cases  the  ulcer  may 
be  very  acute,  and  rapidly  proceed  to  perforation,  and  if  this 
occurs  on  the  anterior  'surface,  general  peritonitis  is  set  up. 
Where,  however,  the  ulcer  is  situated  in  its  more  usual  site 
on  the  posterior  wall,  adhesions  generally  form,  which  tend 
to  limit  the  process,  and  even  if  rupture  does  occur,  the  contents 
are  discharged  into  the  lesser  sac,  to  reach  which  it  is  generally 
best  to  lift  forward  the  transverse  colon,  and  perforate  the 
transverse  mesocolon. 

Adhesions  may  take  place  between  the  stomach  and  other 
abdominal  organs  or  diaphragm.  The  former  may  lead, 
if  the  ulcer  progress,  to  involvement  of  some  large  vessel, 
even  apart  from  those  of  the  stomach,  such  as  the  splenic 
artery  or  portal  vein,  and  cause  death  from  hemorrhage. 
The  latter  may  occasion  septic  affections  of  the  pleurae  or 
pericardium,  the  septic  matter  traversing  the  lymphatics 
which  penetrate  the  diaphragm,  and  sometimes  the  lungs 
or  even  the  heart  may  become  affected.  Adhesions,  by 
limiting  the  general  spread  of  septic  infection,  may  give 
rise  to  a  localized  abscess.  In  this  way  subphrenic  abscesses 
may  arise  between  the  stomach  and  left  lobe  of  the  liver 
below  and  diaphragm  above,  or  an  abscess  may  arise  between 
stomach  and  liver. 

Carcinoma  most  frequently  affects  the  pyloric  region, 
and,  as  a  rule,  is  not  palpable  until  so  far  advanced 
as  to  render  radical  operation  impossible.  Where  car- 
cinoma affects  the  oesophagus,  the  operation  of  gastrostomy 


208  SURGICAL  ANATOMY 

is  frequently  performed,  a  portion  of  stomach  being  drawn 
up  through  the  rectus  muscle,  and  sutured  to  the  skin. 
After  the  wound  has  healed  the  stomach  is  opened,  a  tube 
passed  in,  and  the  patient  fed  through  it.  The  rectus 
abdominis  acts  as  a  sphincter,  preventing  ejection  of  food, 
and  to  enhance  this  effect  the  portion  of  stomach  is  generally 
bent  at  an  angle  as  it  comes  through  the  rectus,  and  is  finally 
brought  out  to  a  new  small  skin  incision  over  the  margin  of 
the  ribs,  the  first  wound  being  stitched  up.  Gastrotomy,  or 
simple  incision  of  the  stomach,  may  be  required  for  treatment 
of  an  ulcer,  removal  of  a  foreign  body,  etc.  Gastrectomy 
consists  of  the  removal  of  a  portion  or  the  whole  of  the 
stomach.  Even  the  latter  operation  has  been  repeatedly 
successful. 

Wounds  of  the  stomach,  particularly  if  inflicted  when  it 
is  distended  with  food,  generally  cause  profound  collapse 
and  death,  with  general  acute  peritonitis  from  escape  of 
the  contents.  Where,  however,  the  stomach  is  empty,  and 
where  the  wound  is  of  a  punctured  nature,  as  from  a  rifle- 
bullet,  the  patient  may,  once  he  gets  over  the  preliminary 
shock,  make  an  uninterrupted  recovery.  It  is  supposed  that 
in  such  cases  the  mucous  membrane  projects  and  forms  a  plug, 
closing  the  wound. 

The  PYLORIC  VALVE,  by  means  of  its  sphincter  muscle, 
controls  the  passage  of  food  from  the  stomach  into  the  in- 
testine, preventing,  as  a  rule,  the  passage  of  food  until  after 
the  peptic  digestion  has  taken  place.  It  is  apparently 
irritated  by  very  acid  stomach  contents,  at  such  times  becoming 
almost  entirely  closed,  and,  at  the  close  of  normal  peptic 
digestion,  it  permits  of  the  passage  of  food  only  in  very  small 
quantities  at  a  time,  so  that  they  may  be  thoroughly  acted  on 
by  the  bilious  and  pancreatic  juices.  The  valve  then 
apparently  plays  an  important  function  in  the  digestive 
process,  but  not  infrequently  it  become  constricted  from 
chronic  irritation,  ulcerative  contraction,  or  carcinomatous 
tumour,  rendering  operative  treatment  necessary.  It  also 
is  occasionally  constricted  congenitally  by  a  form  of  tumour 
which  also  causes  lengthening,  and  is  generally  fatal  unless 
promptly  recognized  and  treated.  Normally,  the  pylorus 
should  admit  the  passage  of  the  forefinger,  but  even  forks 
and  keys  have  been  known  to  pass  through  it.  Needles, 


THE  ABDOMEN  209 

when  swallowed,  appear  to  make  their  way  through  the  wall 
of  the  stomach,  and  may  eventually  project  through  the  skin. 
Where  the  contraction  of  the  pylorus  is  non -malignant,  the 
operative  treatment  may  consist  of  performing  a  pyloro- 
plasty.  Here  a  longitudinal  incision  is  made  through  all  the 
coats,  the  central  points  of  the  upper  and  lower  margin  of 
the  incision  are  caught  by  forceps,  and  pulled  apart  until 
the  wound,  from  being  longitudinal,  becomes  vertical,  and 
then  the  wound  is  sutured  in  the  new  position.  Thus  a  long 
and  narrow  pylorus  is  converted  into  a  short  and  wide  one. 
The  advantage  of  this  operation  is  that  the  pyloric  valve, 
and  also  the  bile  and  pancreatic  ducts,  are  not  disturbed  in 
their  relationship  to  food.  Forcible  dilatation  of  the  pylorus, 
either  through  an  incision  through  the  stomach  wall  or  by 
invaginating  the  wall,  is  dangerous,  and  has  been  almost 
discarded. 

In  carcinoma  of  the  pylorus  the  whole  pylorus  may  be 
removed  (pylorectomy),  and  the  upper  end  of  the  duodenum 
attached  to  the  pyloric  end  of  the  stomach,  which  is  narrowed 
to  fit  it.      For  pyloric  stenosis  some  prefer  the  operation  of 
gastrojejunostomy,   and,   of    course,   this   operation  is  called 
for  where  the  pylorus  is  the  seat  of  an  inoperable  carcinoma. 
The  object  of  this  operation  is  to  make  a  communication 
between  the  stomach,  lying  above  the  transverse  colon  and 
mesocolon,  and  the  jejunum  lying  beneath.      The  abdomen 
having  been  opened,  the  great  omentum  and  transverse  colon 
are  turned  up,  and  the  duodeno-jejunal  junction  sought  for 
to  the  left  of  the  spine  between  the  mesocolon  and  mesenteric 
attachment.     A  portion  is  selected,  a  few  inches  beyond  the 
junction   to   which  -  the   ligament   of    Treitz    (q.v.)    forms    a 
valuable  guide,  and  may  either  be  carried  in  front  of  the 
colon  to  be  attached  to  the  anterior  wall  of  the  stomach 
(anterior  gastro  -  jejunostomy),  or  the  transverse  mesocolon 
is  perforated,  the  posterior  wall  of  the  stomach  exposed,  and 
the  junction  made  at   this  point.     The  latter  operation   is 
probably  the  better, '  regurgitation  of  food  and  vicious  circle 
being    less    apt    to    be    established.     To    obviate    regurgita- 
tion, some  recommend  that  the  jejunum  must  be  so  placed 
that  its  direction  of  peristalsis  shall  correspond  with  that  of 
the   stomach,   while   others   recommend   that   the   bowel   be 
entirely  divided,  the  distal  end  being  stitched  to  the  stomach 

14 


210 


SURGICAL  ANATOMY 


opening,   and   the  proximal  portion  being  opened  into  the 
distal  some  distance  below  the  junction  with  the  stomach. 

The  DUODENUM  is  described  in  three  sections,  the  whole 
being  nearly  a  foot  in  length,  and  describing  a  rough  circle, 
or  sometimes  being  of  a  U  or  V  shape,  with  the  apex  down- 
wards. It  has  been  suggested  that  it  acts  as  a  kind  of  syphon- 


FIG.  26.— TRANSVERSE   SECTION   OF   THE   ABDOMEN   AT  THE   LEVEL  OF 

THE  FIRST  LUMBAR  VERTEBRA. 

(After  Braune.) 


1.  First  lumbar  vertebra. 

2.  Psoas  muscle. 

3.  Erector  spinae,  etc. 

4.  Spleen. 

5.  Kidney. 

6.  Aorta. 

7.  Vena  cava. 

8.  Duodenum. 

9.  Liver. 

10.  Ascending  colon. 

11.  Pancreas,  containing  splenic  vein. 


12.  Transverse  colon. 

13.  Splenic  flexure  and  descending  colon. 

14.  Stomach. 

15.  Round  ligament  of  liver. 

16.  Rectus  abdominis. 

17.  Small  intestine. 

1 8.  Pleura. 

19.  Peritoneum. 

20.  Diaphragm. 

Roman  nu>nera.ls  indicate  ribs. 


tap,  to  prevent  regurgitation  of  gases  into  the  stomach. 
It  is  wider  than  the  jejunum,  and  only  the  first  part  is  movable, 
and  that  slightly.  The  FIRST  is  2  inches  long,  and  passes 
horizontally  backwards  and  to  the  right  on  the  level  of  the 
first  lumbar  vertebra  to  near  the  upper  end  of  the  right  kidney. 
It  is  wider  in  the  centre  than  at  either  extremity,  the  dilated 


THE  ABDOMEN  211 

being  called  the  duodenal  antrum.  The  quadrate 
lobe  of  the  liver  and  gall-bladder  are  above  it,  and  the  neck 
of  the  pancreas  below  it.  At  the  junction  of  the  first  and 
second  portions  is  the  superior  duodenal  flexure.  The  SECOND 
STAGE,  about  3  inches  long,  descends  in  front  of  the  inner 
border  of  the  right  kidney  to  the  level  of  the  third  lumbar 
vertebra,  and  ends  at  the  inferior  duodenal  flexure,  where  it 
joins  the  third  portion.  This  inferior  flexure  is  the  lowest 
portion  of  the  duodenum,  and  sometimes  forms  a  considerable 
pouch.  In  front  it  is  related  to  the  transverse  colon  above 
and  the  small  intestine  below,  and  behind  lie  the  kidney  and 
renal  vessels  and  right  border  of  the  inferior  vena  cava.  The 
bile  and  pancreatic  ducts  open  on  a  common  papilla  on  the 
posterior  and  inner  wall  near  the  termination  of  this  stage. 
The  THIRD  STAGE  is  curved,  running  first  across  the  spine 
from  right  to  left  at  the  level  of  the  third  lumbar  vertebra, 
to  which  it  is  closely  moulded,  and  then,  turning  upwards, 
runs  along  the  left  side  of  the  spine  to  the  level  of  the  second 
lumbar  -vertebra,  where  it  bends  forwards,  forming  the 
duodeno-jejunal  flexure,  which  is  situated  behind,  and  close  to, 
the  duodeno-pyloric  junction.  This  stage  is  related  behind 
to  the  vena  cava,  aorta,  inferior  mesenteric  artery,  left  sper- 
matic and  renal  vessels  and  ureter  ;  in  front  to  the  superior 
mesenteric  vessels,  small  intestine,  transverse  mesocolon  and 
stomach.  It  will  be  noted  that  the  duodenum  is  closely 
related  to  many  important  structures  which  are  liable  to 
become  involved  in  the  various  affections  of  this  part. 
The  relation  of  the  second  part  to  the  kidney  is  thought  to 
explain  the  sickness  and  vomiting  associated  with  movable 
kidney,  the  duodenum  being  dragged  upon  and  partially 
kinked.  The  PERITONEAL  COVERING  of  the  first  portion  is 
as  in  the  stomach.  The  second  stage  is  only  covered  by 
peritoneum  in  front,  and  is  not  covered  where  it  is  crossed  by 
the  transverse  colon,  and  the  third  stage  is  covered  in  front, 
except  where  the  superior  mesenteric  vessels  cross  it.  The 
DUODENO-JEJUNAL  JUNCTION  is  very  firmly  fixed,  being  held 
in  position  by  a  band  of  fibrous  and  unstriped  muscular 
tissue  descending  from  the  left  crus  of  the  diaphragm,  which 
also  supports  the  mesentery  (ligament  or  muscle  of  Treitz). 

The  duodenum  is  frequently  the  seat  of  perforating  ulcers,  in 
some  cases  following  extensive  burns.     These  occur  chiefly 

14—2 


212 


SURGICAL  ANATOMY 


10 


-27 


FIG.  27.— THE  INFRAMESOCOLIC  COMPARTMENT  OF  THE  ABDOMEN.  ON 
THE  RIGHT  A  PORTION  OF  STOMACH,  AND  TRANSVERSE  COLON 
CARRYING  WITH  IT  TRANSVERSE  MESOCOLON,  ARE  SHOWN  TURNED 

UP    AS    FOR    THE    OPERATION    FOR    POSTERIOR    GASTRO  JEJUNOSTOMY. 


1.  Transverse  colon  turned  up. 

2.  Stomach  seen  through 

transverse  mesocolon. 

3.  Pancreas  seen  through 

transverse  mesocolon. 

4.  Kidney  seen  through 

transverse  mesocolon. 

5.  Descending  colon. 

6.  Rectum. 

7.  Bladder. 

8.  CEsophagus. 

9.  Aorta. 

10.  Suprarenal. 

11.  KiJney. 

12.  Inferior  vena  cava. 


13.  Spleen.  23. 

14.  Stomach  turned  up.  24. 

15.  Hepatic  artery.  25. 

16.  Portal  vein.  26. 

17.  I!ile-duct.  27. 

18.  Duodenum. 

19.  Ligament  of  Freitz.  28. 

20.  Superior  mesenteric 

artery.  29. 

zofi.  Middle  colic  artery  30. 

2o/>.  Superior  mesenteric  31. 

vein.  32. 

21.  Descending  aorta. 

22.  Inferior  mesenteric  33. 

artery.  34. 


Spermatic  artery. 

External  iliac  artery. 

Ureter. 

Interior  iliac  artery. 

Anterior  division  of  interior 
iliac. 

Attachment  of  transverse 
mesocolon. 

Head  of  pancreas. 

Iliacus  muscle. 

Psoas  muscle. 

Ilio-hypo^astric  and  in- 
guinal nerves. 

External  cutaneous  nerve. 

Anterior  crural  nerve. 


THE  ABDOMEN  213 

in  the^  first  part  of  the  duodenum,  affecting  particularly 
Brunner's  glands,  and  hence  generally  involve  the  general 
peritoneal  cavity.  Severe  haemorrhage  may  also  occur,  and, 
where  the  affection  is  circumscribed,  a  subphrenic  abscess 
may  form.  Healed  ulcers  may  give  rise  to  stenosis,  and  con- 
genital strictures  are  also  met  with,  particularly  in  the  second 
portion  above  the  common  papilla,  where  the  bowel  may  be 
entirely  obliterated.  Where  cicatrization  involves  the  com- 
mon duct,  serious  jaundice,  with  rapid  emaciation,  would  occur. 
It  is  noteworthy  that  perforating  ulcers  have  also  occurred  after 
a  severe  attack  of  eczema.  A  congenital  pouch  sometimes 
occurs  in  the  second  portion  above  the  common  papilla. 
The  duodenum  is  subject  to  rupture  at  any  part  from  external 
abdominal  injury,  the  general  peritoneum  being  frequently 
not  opened  into.  The  duodenal  blood-supply  is  from  the 
pancreatico  -  duodenal  arteries,  the  superior  being  derived 
from  the  hepatic  gastroduodenal,  and  the  inferior  from  the 
superior  mesenteric. 

As  already  explained,  the  mesentery  consists  of  a  double 
layer  of  peritoneum  running  out  from  the  posterior  abdominal 
wall  to  the  intestine  (of  which  it  forms  the  serous  coat), 
covering  the  vessels,  nerves,  lymphatic  and  lacteal  vessels 
and  glands  supplying  the  bowel.  The  parietal  attachment 
of  the  mesentery  commences  near  the  duodeno-jejunal  junc- 
tion, just  to  the  left  of  the  second  lumbar  vertebra,  where  it 
is  supported  by  the  ligament  of  Tieitz.  Passing  from  the 
third  piece  of  the  duodenum  to  this  point,  there  is  frequently 
seen  a  fold  of  peritoneum,  enclosing  a  triangular  fossa,  with 
the  apex  downwards  and  the  opening  above,  just  below  the 
duodeno-jejunal  junction.  The  opening,  normally,  would 
admit  the  tip  of  the  finger,  and  through  it  a  retro-peritoneal 
hernia  may  occur,  the  jejunum  pushing  its  way  down  between 
the  posterior  wall  of  the  abdomen  and  the  peritoneum. 
Such  herniae  may  be  very  large,  occupying  the  left  side,  and 
reaching  perhaps  the  promontory  of  the  sacrum.  Several 
somewhat  similar  fossae  may  occur  in  this  region,  but  that 
described  is  the  most  constant.  From  the  point  of  its  com- 
mencement the  mesenteric  attachment  runs  downwards  and 
to  the  right  for  about  6  inches  to  the  iliac  fossa,  where  it  ends 
indefinitely.  The  upper,  or  right,  layer  is  continuous  with  the 
under  layer  of  the  transverse  mesocolon  ;  the  lower,  or  left, 


214  SURGICAL  ANATOMY 

layer  runs  down  over  the  descending  colon,  forms  the  sigmoid 
mesentery,  and  descends  into  the  pelvis.  This  oblique  attach- 
ment is  of  importance,  as  it  directs  effusions  from  the  upper 
portion  of  the  abdomen  to  the  right  iliac  fossa.  Thus,  in  a 
case  of  perforating  pyloric  ulcer  the  extruded  matter  may 
be  conducted  to  the  right  inguinal  region,  over  which  the 
patient  may  chiefly  complain  of  pain,  thereby  causing  sus- 
picion of  appendicitis.  The  obliquity  ma*y  also  be  taken 
advantage  of  surgically  in  determining  which  is  the  upper 
end  of  a  particular  loop  of  bowel..  If  the  loop  be  straightened 
out,  and  care  be  taken  that  its  mesentery  is  not  twisted, 
then  the  end  nearer  the  thorax  is  the  upper.  The  average 
length  of  the  mesentery  is  about  8  inches,  while  the  lowest 
part,  which  supplies  some  5  feet  of  bowel  about  the  jejuno- 
ileal  junction,  is  about  10  inches.  This  portion  of  bowel, 
therefore,  generally  hangs  lowest,  and  is  frequently  found  in 
hernia.  It  is  worthy  of  note,  however,  that  where  the 
mesentery  is  normal  in  attachment  and  length,  no  portion 
of  bowel  will  readily  come  through  the  inguinal  or  femoral 
rings.  The  mesentery  is  relatively  longer  prior  to  puberty, 
and  permits  descent  of  the  bowel  more  freely  on  the  right 
side.  In  acquired  hernia  Lockwood  states  that  the  mesen- 
teric  attachment  generally  is  found  to  have  descended,  causing 
enteroptosis  (prolapse  of  the  mesentery),  rather  than  to  have 
lengthened.  Apertures,  congenital,  or  acquired  from  injury, 
sometimes  occur  in  the  mesentery,  particularly  the  portion 
connected  with  the  lower  ileum,  through  which  a  knuckle 
of  the  bowel  may  pass  and  become  strangulated,  and  bowel 
has  even  become  strangulated  through  the  foramen  of 
Winslow.  Tubercle  frequently  attacks  the  peritoneum, 
generally  causing  tubercular  peritonitis,  while  it  may  cause 
enlargement  and  caseation  of  the  mesenteric  glands.  In  some 
cases  the  mesentery  becomes  very  much  contracted,  drawing 
the  bowel  close  up  to  its  attachments,  and  thus  forming  a 
shrunken  and  compact  mass  (peritonitis  deformans).  As  a 
result  of  old  tubercular  disease  and  formation  of  adhesions, 
fibrous  bands  are  frequently  produced,  which  are  sometimes 
a  cause  of  internal  strangulation  of  bowel. 

The  SMALL  INTESTINE  between  the  duodenum  and  caput 
caecum  is  on  an  average  about  22  feet  long,  and  is  divided 
into  two  portions — jejunum  and  ileum — the  first  being  about 


THE  ABDOMEN  215 

8  feet,  and  the  latter  14  feet,  in  length.  There  is  no  definite 
point  of  junction  between  the  two,  the  transition  being 
gradual.  The  jejunum  is  about  ij  inches  in  diameter,  and  the 
ileum  i  inch,  but  muscular  contraction  may  render  the  bowel 
very  narrow,  while  gaseous  distension  may  render  it  very 
wide.  The  jejunum  is  about  J  inch  wider,  thicker  walled, 
heavier,  and  more  vascular  than  the  ileum.  With  regard 
to  the  arrangement  of  the  bowel  in  the  abdominal  cavity, 
as  a  rule  the  coils  on  the  left  side  of  the  spine  and  high  up  are 
jejunum,  while  these  in  the  pelvis  and  right  iliac  fossa  are 
ileum.  In  the  region  of  the  pubes  may  frequently  be  found 
that  portion  of  bowel  with  the  longest  mesentery  (about 
the  jejuno-ileal  junction),  and  also  the  lower  portion  of  the 
ileum. 

It  is  often  of  importance  in  abdominal  operations  to 
determine  roughly  to  what  portion  of  the  intestinal  tract  a 
loop  which  has  been  picked  up  belongs.  It  is  not  easy 
to  do  this,  but  some  guiding  points  may  be  mentioned. 
The  valvula  conniventes,  or  transverse  folds  of  mucous 
membrane,  are  most  marked  in  the  upper  port'on  of  the 
jejunum  ;  are  fewer  beyond  that  point ;  and  absent,  or  almost 
so,  beyond  the  middle  of  the  ileum.  These  may  be  seen  by 
transmitted  light,  if  the  bowel  be  fairly  translucent.  The 
Peyer's  patches,  which  are  oblong  collections  of  lymphoid 
tissue,  about  i  inch  long  and  J  inch  broad,  situated  opposite 
the  mesenteric  attachment,  and  numbering  between  twenty 
and  thirty  in  all,  are  larger  and  more  numerous  in  the  ileum 
than  in  the  jejunum.  Further,  the  vessels  supplying  the 
lower  ileum  form  one  or  even  two  sets  of  arches  in  the  mesen- 
tery, prior  to  running  into  the  bowel,  and  the  mesentery 
becomes  progressively  more  fat-laden  toward  the  lower  end, 
sometimes  so  much  so  as  to  obscure  the  vascular  arches. 

Peyer's  patches  are  favourite  sites  for  both  tubercle  and 
typhoid  bacilli  to  settle  in  and  cause  ulcer ation.  The  former 
rarely  perforate  the  serous  coat,  but  do  not  respect  the 
anatomical  margins  of  the  patch,  tending  to  extend  circularly 
round  the  lumen  of  the  gut,  and  hence,  in  healing,  to  cause 
stricture.  The  latter  are  prone  to  perforation,  remain  localized 
to  the  patch,  and  heal  generally  with  a  flat  cicatrix,  stricture 
being  an  uncommon  sequela. 

Lieberkiihris  glands  occur  throughout  the  entire  intestinal 


216  SURGICAL  ANATOMY 

tract,  and  are  a  frequent  starting-point  both  for  adenoma 
and  carcinoma  of  the  intestine.  Where  it  is  necessary  from 
gangrene  or  malignant  growth  to  remove  a  portion  of  bowel 
(enter  ectomy) ,  care  should  be  taken  to  allow  healthy  mesentery 
to  project  beyond  the  cut  end  of  the  bowel  on  either  side,  and, 
further,  to  cut  the  bowel  obliquely,  removing  more  of  the  side 
opposite  the  mesenteric  attachment,  the  object  of  these 
precautions  being  to  secure  sufficient  blood-supply.  In 
suturing  (enterorraphy)  care  is  taken  to  apply  serous  surfaces 
to  one  another,  as  these  unite  readily.  The  position  where 
delay  in  healing  generally  occurs  is  at  the  mesenteric  attach- 
ment, where,  owing  to  divergence  of  the  two  layers  of  the 
mesentery  (^  inch),  there  is  no  serous  coat.  As  a  rule,  if 
more  than  a  third  of  the  total  length  of  the  intestine  be  re- 
moved, the  patient's  nutrition  suffers.  It  may  be  necessary 
to  open  a  piece  of  bowel  (enterotomy)  to  remove  an  impacted 
body,  or  to  short  circuit  a  piece  involved  in  a  tumour. 

Wounds  of  the  small  intestine  are  generally  more  serious 
the  nearer  the  stomach  they  occur.  Where  the  wound  is 
small,  particularly  if  punctured,  no  harm  will  probably  result. 
Thus  the  bowel  has  been  frequently  punctured  for  tympanites 
without  untoward  consequences,  and,  even  when  the  wound 
is  a  little  larger,  the  mucous  membrane  generally  protrudes 
into  and  fills  up  the  wound.  This  protrusion  of  mucous 
membrane,  together  with  muscular  contraction,  may  prevent 
extrusion  of  material  even  in  small  incised  wounds.  As  a  rule, 
longitudinal  wounds  gape  more  than  do  transverse,  the  circular 
layer  being  the  stronger.  Transverse  wounds  gape  most 
when  situated  opposite  to  the  mesenteric  attachment,  and 
jejunal  wounds  generally  gape  more  than  those  of  the  ileum. 

VESSELS. — Both  jejunum  and  ileum  are  supplied  by  the 
superior  mesenteric,  from  which  some  fifteen  to  twenty  branches 
run  forward  between  the  mesenteric  layers,  form  numerous 
anastomosing  arches,  and  then  give  off  little  straight  vessels 
which  run  forward  to  the  bowel,  and  then  bifurcate  at  the 
mesenteric  attachment,  one  little  vessel  running  along  either 
side  of  the  bowel  wall,  first  subperitoneally,  and  then  in  the 
submucous  coat.  The  veins  are  similarly  arranged,  and  run 
to  join  the  superior  mesenteric  which,  joining  with  the  splenic, 
forms  the  portal  vein.  The  LYMPHATICS,  or  lacteals,  as  they 
are  here  called,  commencing  in  the  villi  of  the  mucous  mem- 


THE  ABDOMEN  217 

brane,,  and  as  lymphatic  sinuses  surrounding  the  bases  of 
the  solitary  glands,  form  plexuses  between  each  of  the  coats, 
submucous  and  subserous,  and  also  between  the  two  muscular 
coats,  then  pass  between  the  mesenteric  layers  to  the  MESEN- 
TERIC  GLANDS  (which  may  number  over  100,  the  larger 
ones  lying  close  to  the  mesenteric  attachment),  and  then, 
uniting  to  form  one  or  more  large  vessels,  open  into  the 
RECEPTACULUM  CHYLi,  which  lies  onthe  right  side  of  the  body 
of  the  second  lumbar  vertebra.  In  tubercular  disease  of  the 
intestine  the  infection  is  frequently  carried  to  these  mesenteric 
glands,  causing  tabes  mesenterica.  The  glands  may  become 
very  large,  and  caseate,  or,  later,  they  may  form  large  cal- 
careous masses.  The  mesentery  may  shrink,  causing  peri- 
tonitis de for  mans,  and  even  in  less  severe  cases,  symptoms 
resembling  intestinal  obstruction  frequently  arise.  Chyle 
cysts,  which  may  attain  a  large  size,  arise  probably  from 
blocking  of  some  of  the  ducts.  The  NERVES  are  derived 
chiefly  from  the  solar  plexus,  a  few  fibres  coming  from  the 
right  vagus,  and  pass  as  the  superior  mesenteric  plexus,  along 
with  the  superior  mesenteric  artery,  to  the  bowel,  where 
they  form  intermuscular  (Auerbach's)  and  submucous  (Meis- 
sner's)  plexuses. 

Meckel's  diverticulum  is  produced  by  persistence  of  the 
intestinal  end  of  the  vitello-intestinal  duct  ;  is  situated  on 
the  ileum,  some  i  to  4  feet  from  the  ileo-caecal  valve ;  and 
consists  of  a  diverticulum  of  varying  length,  but  generally 
only  a  few  inches  long,  of  the  same  structure  and  calibre  as 
the  bowel  from  which  it  springs.  It  may  terminate  in  a  free 
extremity,  or  may  be  continued  toward  the  umbilicus  as  a 
fibrous  cord.  It  is~met  with  in  about  2  per  cent,  of  bodies, 
and  is  chiefly  of  importance  from  its  tendency  to  cause 
intestinal  obstruction :  by  twisting  round  some  other  portion 
of  bowel ;  from  its  tip  becoming  adherent,  and  a  loop  of  bowel 
slipping  under  the  bridge  so  formed ;  from  contraction  of  its 
adhesions,  dragging  upon  and  kinking  the  ileum  from  which 
it  springs  ;  or,  by  causing  intussusception. 

THE  LARGE  INTESTINE.  —  The  C^CUM  is  that  portion 
of  large  intestine  which  lies  below  the  entrance  of  the 
ileum.  It  is  normally  situated  in  the  right  iliac  fossa,  its 
most  dependent  part  midway  between  the  anterior  iliac 
spine  and  symphysis  pubis,  and  measures  2j  inches  ver- 


2i8  SURGICAL  ANATOMY 

tically,  and  3  inches  in  diameter.  When  empty  it  is 
generally  covered  by  other  loops  of  bowel,  but  when  full 
lies  in  contact  with  the  abdominal  wall.  In  herbivora  the 
caecum  is  very  large,  and  developmentally  in  man  the  appendix 
forms  the  tapering  extremity  of  the  caecum,  this  '  infantile 
type  '  sometimes  persisting.  The  caecum,  like  the  colon,  is 
possessed  of  three  longitudinal  bands,  one  of  which  is  situated 
anteriorly,  and  the  others  postero-externally  and  internally 
respectively.  The  caecum  falls  from  these  bands  in  saccular 
folds,  and,  in  addition,  owing  to  shortness  of  the  internal  band, 
it  is  curved,  with  the  concavity  to  the  left.  In  the  adult 
type  this  curving  becomes  more  marked,  as  does  likewise  the 
sacculation  between  the  anterior  and  postero-external  bands, 
until  finally  this  saccule  becomes  the  most  dependent  part, 
and  the  appendix  appears  tucked  up  and  attached  to  the 
inner  and  posterior  wall.  As  these  bands  are  continued  into 
the  appendix,  the  anterior  one  is  sometimes  taken  as  a  guide 
to  the  appendix.  It  should  be  remembered  that  develop- 
mentally  the  caecum  first  lies  on  the  left  side,  and  then  crosses 
to  the  right,  lying  at  first  in  front  of  the  right  kidney,  and  then 
descending  toward  the  pelvis.  This  fact  may  account  for 
the  caecum  being  found  occasionally  in  left-sided  inguinal 
and  umbilical  herniae.  Further,  as  the  caecum  is  generally 
entirely  invested  with  peritoneum,  it  is  comparatively  mobile. 
Sometimes  it  retains  its  foetal  mesentery,  and  from  this  cause, 
also,  may,  along  with  the  appendix,  form  the  contents  of 
a  hernia  on  the  right,  or  even  on  the  left,  side,  or  become 
affected  by  volvulus.  Foreign  bodies  may  sometimes  lodge, 
and  concretions  may  form,  in  the  caecum,  and  cause  ulceration. 
Where  there  is  obstruction  in  the  large  intestine,  the  caecum 
tends  to  become  distended  with  faecal  matter,  sometimes 
becoming  very  large,  and  occupying  a  large  portion  of  the 
abdominal  cavity.  An  examination,  therefore,  of  the  caecum 
may,  in  a  case  of  doubt,  assist  in  determining  whether 
an  obstruction  exists  above  or  below  the  ileo-ccecal  valve.  If 
the  former,  the  caecum  will  be  normal ;  if  the  latter,  it  will 
probably  be  distended  ;  and  in  such  cases  it  is  prone  to  stercoral 
ulceration,  which  may  lead  to  perforation.  Dysenteric  and 
tubercular  ulcers  also  occur  in  it. 

The  VERMIFORM   APPENDIX  in  the  adult  is  situated  on 
the  inner  and  posterior  aspect  of  the  caecum,  and  is  normally 


THE  ABDOMEN  219 

about^J  inches  long,  and  about  J-  inch  in  diameter.  Its 
position  is  very  variable,  even  when  the  caecum  retains  its 
normal  situation,  and  it  also  varies  greatly  in  length. 
It  may  lie  curled  up  behind  the  caecum  and  ileum,  or  its 
extremity  may  extend  over  the  brim  into  the  pelvis,  or  even 
be  found  on  the  left  side  of  the  abdomen,  or  up  under  the  liver. 
The  position  of  its  orifice  on  the  posterior  and  inner  caecal 
wall  is  about  i  inch  below  the  ileo-caecal  valve,  and  generally 
presents  a  valved  aperture.  It  is  enveloped  in  peritoneum, 
its  mesentery,  which  is  derived  from  that  supplying  the 
lower  end  of  the  ileum,  extending  generally  to  the  tip,  although 
the  terminal  position  may  be  represented  by  a  slight  ridge. 
Shortness  of  this  mesentery  may  cause  bends  of  the  appendix. 

The  peritoneum  in  this  neighbourhood  presents  several 
small  FOSSAE,  which  are  possibly  of  importance  in  relation  to 
herniae  and  appendicitis.  One  of  these,  the  ileo-cacal  fossa, 
whose  orifice  is  directed  away  from  the  caecum,  is  situated 
below  the  ileum,  in  the  angle  between  it  and  the  caecum. 
It  is  bounded  behind  by  the  mesoappendix,  and  in  front  by  a 
fold  of  peritoneum  (the  ileo-caecal  fold),  which  runs  from  the 
ileum  down  to  join  the  front  of  the  mesoappendix.  The 
ileo-colic  fossa,  similar  but  smaller,  is  situated  on  the  upper 
surface  of  the  ileum,  being  bounded  behind  by  the  mesen- 
tery of  the  ileum,  and  in  front  by  a  small  fold  of  peri- 
toneum (the  ileo-colic  fold).  Retro-colic  fossce  are,  occasionally, 
present,  and  are  seen  by  turning  the  caecum  upwards.  They 
lie  behind  the  beginning  of  the  colon  on  either  its  outer  or 
inner  margin,  or  both.  When  they  are  present,  the  appendix 
is  said  frequently  to  lodge  in  them,  and  so  be  more  prone  to 
appendicitis,  presumably  from  becoming  caught. 

In  structure  the  appendix  closely  resembles  the  large  intestine. 
The  lymphatic  follicles  are  most  prominent  in  younger  subjects, 
and  occur  particularly  at  the  distal  portion  of  the  appendix. 

The  ileo-colic  division  of  the  superior  mesenteric  artery 
branches  to  supply  the  lower  end  of  the  ileum,  caecum,  appen- 
dix, and  portion  of  the  ascending  colon.  The  branch  which 
supplies  the  anterior  surface  of  the  caecum  runs  down  in  the 
ileo-colic  fold,  and  gives  off  the  appendicular  artery,  which 
runs  behind  the  ileum  to  reach  the  mesoappendix.  It  in 
turn  gives  off  a  recurrent  branch,  which  runs  in  the  ileo-caecal 
fold  to  reach  the  ileum,  and  then  runs  forward  supplying  the 


220  SURGICAL  ANATOMY 

appendix  to  its  tip  by  means  of  numerous  branches.     The 
veins  are  similar,  and  empty  into  the  superior  mesenteric. 

The  nerves  of  the  caecum  and  appendix  are  derived  from  the 
superior  mesenteric  plexus,  and  the  lymphatics  pass  to  the 
mesocolic  glands,  lying  behind  the  ascending  colon.  The 
common  nerve-supply  of  ileum  and  appendix  should  be  noted. 
Thus  in  operative  cases  it  has  been  seen  that,  when  the 
lower  portion  of  the  ileum  is  stimulated,  the  secretion  of  the 
appendix  comes  in  little  jets,  and,  as  the  ileo-caecal  valve 
directs  the  intestinal  contents,  as  they  enter  the  caecum,  over 
the  mouth  of  the  appendix,  they  are  thoroughly  mixed  with 
this  secretion.  While  this  secretion  may  have  a  purely 
digestive  function,  it  has  been  suggested  that  the  appendix 
may  also  exist  as  a  culture  chamber  for  the  Bacillus  coli,  and 
that  it  impregnates  the  contents  with  the  bacilli  at  this  point 
(Macewen).  Certainly  a  number  of  obscure  digestive  troubles 
have  been  traced  to  affections  of  the  appendix,  and  it  is  well 
known  that  obstinate  constipation  frequently  follows  the 
removal  of  the  appendix.  It  has  further  been  noted  in  actual 
cases  that  mental  impressions  have  a  marked  effect  upon  the 
secretion  of  appendix  and  caecum,  bad  news  producing  an 
entire  cessation  of  secretion  for  some  hours.  Thus  the 
mental  condition  as  a  cause  of  indigestion  cannot  be  dis- 
regarded. In  cases  of  mucous  colitis  it  is  frequently  of  advan- 
tage to  be  able  to  wash  out  the  colon,  and  this  is  readily  done 
by  bringing  out  the  appendix  through  the  abdominal  wall, 
cutting  off  its  tip  after  it  has  contracted  adhesions,  and  then 
irrigating  by  means  of  a  narrow  tube  passed  down  through 
the  appendix  (Macewen).  In  such  cases  it  is  possible  to 
observe  the  appendix,  and  it  is  worthy  of  note  that,  save  in 
cases  of  severe  purgation,  faecal  matter  rarely  finds  its  way 
into  the  appendix.  Even  in  such  purgation  only  a  slight 
brown  stain  generally  results.  Foreign  bodies,  such  as  pins 
and  orange-pips,  do  occasionally  find  their  way  into  the 
appendix,  but  generally  such  bodies  are  composed  of  gradually 
accumulated  faecal  matter,  and  are  termed  coproliths. 

The  appendix  is  a  frequent  seat  of  inflammatory  and  sup- 
purative  mischief,  which  sometimes  subsides  after  the  pus  has 
become  discharged  into  the  bowel,  or  may  proceed  toulcer ation , 
or  gangrene,  with  localized  or  generalized  peritonitis.  As  already 
explained,  the  omentum  and  various  bowel  loops  frequently 


THE  ABDOMEN  221 

take  nart  in  walling  off  an  abscess  arising  in  connection  with 
the  appendix,  and  thus  preventing  general  peritonitis.  Such 
appendicular  abscesses  may  be  found  in  almost  any  portion 
of  the  abdomen,  and  are  frequently  met  with  in  the  pelvis, 
and  less  commonly  up  under  the  liver,  or  diaphragm,  or 
on  the  left  side.  A  subphrenic  abscess  may  arise  from  lym- 
phatic extension  from  the  appendix.  When  the  appendix 
is  inflamed,  it  may  become  attached  to  the  ovary,  and  fre- 
quently it  is  difficult  to  discriminate  between  the  two  organs 
as  the  seat  of  pain.  From  the  involvent  of  the  psoas  muscle 
and  anterior  crural  nerve  the  thigh  is  frequently  flexed,  and  pain 
is  referred  to  the  inside  of  the  knee,  thus  simulating  hip  disease. 
Again,  when  the  abscess  is  up  under  the  liver,  the  condition 
may  be  diagnosed  as  one  arising  in  connection  with  liver  or 
kidney,  etc. 

Why  the  appendix  should  thus  be  affected  by  in- 
flammatory mischief  is  not  easy  to  explain.  Its  blind 
extremity,  narrow  lumen,  power  of  movement,  unequal 
length  and  position  of  its  mesentery,  and  abundant  supply  of 
Bacillus  coli  in  its  interior,  may  all  be  predisposing  causes. 
In  operations  for  appendicitis  an  incision  is  generally  made 
with  its  centre  over  McBurney's  point,  situated  2  inches  from 
the  anterior  superior  spine  on  a  line  from  the  spine  to  the 
umbilicus.  The  incision  runs  obliquely  downwards  and 
inwards,  and  the  abdominal  muscles,  where  possible,  are 
split,  rather  than  cut,  in  the  direction  of  their  fibres.  Where 
a  circumscribed  abscess  exists,  an  incision  farther  out  is  generally 
better,  it  being  frequently  possible  to  evacuate  the  abscess 
without  opening  the  general  peritoneal  cavity.  The  scar  of 
a  wound  which  has  healed  by  connective  tissue  is  liable  to 
stretch  and  cause  a  ventral  hernia.  Such  herniae  occur 
probably  most  often  through  appendix  scars,  where,  owing 
to  suppuration,  the  wound  has  been  kept  open  and  allowed 
to  granulate. 

The  normal  position  of  the  ileo-caecal  valve  is  indicated 
on  the  surface  by  a  point  slightly  above  that  midway  between 
the  anterior  superior  spine  and  umbilicus.  It  is  situated 
somewhat  posteriorly,  at  the  junction  of  caecum  and  colon, 
and  consists  of  a  narrow  opening  about  |  inch  long,  the  long 
axis  lying  horizontally,  and  the  aperture,  which  is  bounded 
by  upper  and  lower  crescentic  margins,  looking  forwards  and 


222  SURGICAL  ANATOMY 

to  the  right.  At  the  junction  of  the  upper  and  lower  margins 
at  each  end  of  the  valve,  a  ridge,  or  frenula,  extends  round  the 
caecum.  While  the  peritoneal  and  longitudinal  muscular 
coats  of  the  bowel  pass  sharply  from  the  ileum  to  the  colon, 
the  mucous  and  part  of  the  circular  muscular  coats  are  in- 
vaginated  at  the  valve  into  the  caecum  to  form  the  above- 
mentioned  crescentic  margins,  a  markedly  pouting  mouth 
being  produced,  which  directs  the  bowel  contents  over  the 
orifice  of  the  appendix  as  they  enter  the  caecum.  This  mouth 
is  also  supposed  to  act  in  preventing  regurgitation  of  food  into 
the  ileum,  since,  as  the  caecum  distends  and  the  frenula 
becomes  tight,  the  valve  is  mechanically  closed  for  the  time 
being.  It  is  at  this  valve  that  intussusception  most  fre- 
quently occurs,  the  narrower  ileum  being,  as  a  rule,  projected 
into  the  wider  colon,  carrying  the  valve  inwards  as  its  apex 
(ileo-caecal) .  To  such  an  extent  may  the  intussusception  go 
that  the  valve  may  ultimately  appear  at  the  anus.  Occa- 
sionally the  valve  retains  its  position,  and  the  ileum  alone 
forms  the  intussusception  (ileo-colic)  ;  this,  however,  is  not 
common. 

The  COLON,  commencing  at  the  ileo-caecal  valve,  and 
terminating  at  the  junction  with  the  rectum,  opposite  the 
front  of  the  body  of  the  third  sacral  vertebra,  is  fully  3  feet 
long,  and  has  a  diameter  ranging  from  2 J  inches  at  the  caecum 
to  ij  inches  at  the  sigmoid  flexure,  its  general  shape  being 
that  of  a  capital  M.  The  ascending  and  descending  colon 
may,  or  may  not,  have  a  mesocolon,  the  proportions  being 
about  equal,  while  a  mesocolon  is  rather  more  common  on 
the  left  than  on  the  right.  As  a  mesocolon  renders  the 
operation  of  lumbar  colotomy  difficult,  this  would  be  one 
reason  for  avoiding  that  operation. 

The  ascending  colon,  about  8  inches  long,  ascends  in  front 
of  the  fascia  iliaca,  the  fascia  over  the  quadratus  lumborum, 
and  the  lower  and  outer  portion  of  the  right  kidney  to  the 
under  surface  of  the  right  lobe  of  the  liver,  where  is  situated 
the  hepatic  flexure,  at  which  the  ascending  communicates 
with  the  transverse  colon.  As  it  ascends  it  curves  slightly 
with  the  concavity  to  the  left,  and  while  it  is  quite  superficial 
near  its  commencement,  the  hepatic  flexure  is  deeply  placed, 
and  is  therefore  not  easily  palpable.  Where  the  caecum  has 
not  descended,  the  ascending  colon  is  absent. 


THE  ABDOMEN  223 

The  HEPATIC  FLEXURE  is  generally  an  acute  bend,  situated 
between  the  lateral  abdominal  wall  externally  and  the 
descending  duodenum  internally,  which  rests  on  the  kidney 
posteriorly,  and  impresses  the  liver  above.  It  may  be 
supported  by  the  hepato-colic  ligament,  a  peritoneal  band, 
which  is  occasionally  given  off  to  it  from  the  right  extremity 
of  the  gastro-hepatic  omentum. 

Commencing  at  the  hepatic  flexure,  which,  as  stated,  is  deeply 
placed,  the  transverse  colon,  which  is  generally  about  20  inches 
long,  runs  forward  and  to  the  left,  thus  once  more  becoming 
superficial  and  therefore  palpable.  While  the  general  direction 
of  the  transverse  colon  is  upwards  towards  the  splenic  flexure, 
which  is  placed  on  a  higher  level  than  the  hepatic,  its  shape 
varies  considerably,  its  right  side  portion  being  compara- 
tively fixed  while  the  left  portion  is  largely  influenced  by  the 
movements  of  the  stomach.  Normally,  the  umbilicus  should 
indicate  the  lower  border  of  the  transverse  colon,  which, 
however,  sometimes  descends  much  below  this,  and  even  below 
the  pubis,  where  it  may  contract  adhesions  to  the  pelvic 
organs  (ptosis).  It  is  not  infrequently  found  in  umbilical 
hernia,  and  in  hernias  through  the  foramen  of  Winslow,  and 
has  been  present  in  a  left  inguinal  hernia,  while  its  presenting 
through  incisions  made  for  removal  of  the  appendix  or  left 
inguinal  colotomy  has  led  to  considerable  confusion.  At  the 
hepatic  end  it  is  in  relation  to  the  liver  and  gall-bladder, 
and  hepatic  abscesses  have  discharged  into  the  transverse 
colon,  and  fistulas  have  occurred  between  the  gall-bladder 
and  transverse  colon  from  large  gall-stones  ulcerating  through. 
Posteriorly,  also,  at  this  part  it  is  related  to  the  descending 
duodenum,  to  the  front  of  which,  as  well  as  the  head  of  the 
pancreas,  it  is  generally  fairly  fixed  either  by  short  mesentery 
or  areolar  tissue.  Beyond  this  point  the  transverse  meso- 
colon  develops,  and  then  the  bowel  becomes  free,  until 
close  to  the  splenic  flexure.  Owing  to  its  comparative 
freedom  of  movement,  the  transverse  colon  may  occasionally, 
and  particularly  when  distended  with  gas,  lie  in  front  of  both 
stomach  and  liver,  thus  tending  to  obliterate  the  area  of  liver 
dulness. 

At  the  SPLENIC  FLEXURE  the  bowel  runs  upwards  and 
backwards  once  again,  becoming  deeply  placed,  until  the 
base  of  the  spleen  is  reached,  when  it  bends  sharply  down- 


224  .SURGICAL  ANATOMY 

wards  into  the  descending  colon.  At  this  point  the  colon  lies 
deeply  behind  the  stomach  and  under  the  spleen,  being  kept 
in  position  by  the  phreno-colic  ligament  which  runs  to  it 
from  the  diaphragm.  Dragging  upon  this  ligament  is  sup- 
posed to  be  the  cause  of  pain  referred  to  the  left  scapular 
region  in  some  cases  of  chronic  constipation.  The  diaphragm 
is  affected,  and  so  impressions  are  conveyed  to  the  cervical 
cord  by  the  left  phrenic  nerve,  whence  they  are  referred  to  the 
distribution  of  the  descending  supra-acromial  nerves. 

The  TRANSVERSE  MESOCOLON  conveys  the  blood-supply  to 
the  transverse  colon,  and  also  forms  a  diaphragm  at  the  level 
of  the  descending  duodenum  and  pancreas,  which  extends 
laterally  to  the  kidneys  and  anteriorly  to  the  transverse  colon, 
dividing  the  abdominal  cavity  into  two  compartments,  the 
lower  of  which  contains  the  whole  of  the  small  intestine. 

The  descending  colon,  some  9  or  10  inches  long,  extends  from 
the  splenic  flexure  to  the  inner  border  of  the  psoas  muscle  at 
the  brim  of  the  pelvis.  Curving  at  first  downwards  and 
inwards  along  the  outer  border  of  the  kidney,  it  runs  vertically 
to  the  iliac  crest  (this  portion  being  about  4  to  5  inches  long  : 
descending  colon  proper),  and  then  passes  downwards  and 
inwards  in  front  of  the  iliacus  muscle,  crosses  the  psoas  a 
little  above  the  level  of  Poupart's  ligament,  and  terminates 
at  the  pelvic  brim  in  the  pelvic  colon  (this  ILIAC  COLON  portion 
is  about  5  inches  long).  The  descending  colon,  like  the  iliac, 
is  generally  devoid  of  mesentery,  being  only  covered  by 
peritoneum  on  the  front  and  sides.  Both  portions  are  gener- 
ally separated  by  loops  of  small  bowel  from  the  anterior 
abdominal  wall,  and  they  are  narrower  than  the  ascending 
colon. 

The  pelvic  colon,  which  is  continuous  above  with  the  iliac 
colon  and  below  with  the  rectum,  constitutes  the  SIGMOID 
FLEXURE  proper.  It  commences  at  the  inner  border  of  the  left 
psoas  by  crossing  the  external  iliac  vessels  and  dipping  over  the 
pelvic  brim,  and  then  runs  in  the  pelvis  from  left  to  right,  rest- 
ing on  the  bladder  or  uterus.  It  then  turns  backwards  along  the 
light  posterior  wall  of  the  pelvis  till  it  reaches  the  middle  line, 
where,  at  the  level  of  the  third  piece  of  the  sacrum,  it  becomes 
continuous  with  the  rectum.  It  thus  forms  a  loop  which  is 
supplied  with  a  COMPLETE  MESENTERY,  which  permits  of  con- 
siderable movement,  its  position  varying  with  the  amount  of 


THE  ABDOMEN  225 

distension  of  the  bladder,  etc.  This  portion  varies  in  length 
from  J  foot  to  nearly  3  feet,  the  average  being  about  17  inches 
When  very  short,  its  course  is  more  simple,  while,  'when  long,  it 
may  describe  an  S.  When  of  normal  length  and  shape,  the 
two  ends  of  the  sigmoid  are  some  3  inches  apart.  Sometimes, 
however,  they  may,  from  natural  or  pathological  causes, 
become  approximated,  and  then  the  condition  known  as 
VOLVULUS,  in  which  the  two  ends  of  the  loop  become  twisted 
upon  one  another,  is  apt  to  occur.  Here  the  bowel  becomes 
enormously  distended,  while  its  vascular  supply  is  cut  off,  and 
gangrene  may  supervene.  Faecal  accumulations,  carcinoma 
recti,  etc.,  may  also  cause  distension,  the  loop  resembling  a 
greatly  dilated  stomach.  In  some  cases  of  great  distension 
it  may  rise  quite  out  of  the  pelvis,  and  even  cause  palpitation 
and  dyspnoea  by  pressing  upon  the  diaphragm.  The  mesen- 
tery of  the  loop  is  fan-shaped,  its  attachment,  having  the  shape 
of  an  inverted  V,  running  up  the  inner  border  of  the  left  psoas 
to  the  bifurcation  of  the  common  iliac,  and  then  turning 
sharply  downwards  to  descend  over  the  sacral  promontory 
and  front  of  the  sacrum  to  the  third  piece,  where  it  ends.  At 
the  apex  of  the  inverted  angle  there  is  a  small  '  intersigmoid 
fossa,'  which  lies  under  the  mesentery,  admits  the  tip  of  the 
little  finger,  and  has  rarely  been  the  seat  of  strangulated  hernia. 
On  account  of  its  freedom  of  movement,  this  portion  of  bowel 
is  generally  selected  in  the  operation  for  inguinal  colotomy. 
(This  operation  has  almost  entirely  displaced  the  older  opera- 
tion of  lumbar  colotomy,  in  which  the  bowel  is  opened  from 
behind  through  an  incision  parallel  to  the  last  rib,  and  passing 
through  a  point  midway  between  the  centre  of  the  crest  of  the 
ilium  and  the  tip  of 'the  last  rib.  The  structures  cut  through 
are  the  latissimus  dorsi  and  external  oblique,  internal  oblique, 
transversalis  muscle,  fascia  lumborum,  and  transversalis 
fascia,  and  the  bowel  is  exposed  between  the  psoas  and  quad- 
ratus  lumborum.) 

In  INGUINAL  COLOTOMY  an  incision  about  2  inches  long  is 
made  at  right  angles  to  a  line  joining  the  anterior  superior 
spine  and  umbilicus,  and  ij  inches  from  the  anterior  superior 
spine.  The  two  obliques  and  transversalis  are  split,  the 
peritoneum  opened  sufficiently  to  admit  the  finger,  and  the 
sigmoid  is  drawn  up  and  secured.  Generally  a  glass  rod  is 
passed  through  its  mesentery,  partly  to  keep  it  up,  and  partly 

15 


226  SURGICAL  ANATOMY 

to  form  a  spur,  which  will  tend  to  prevent  faecal  matter  passing 
beyond  that  point.  It  is  generally  wise  to  stitch  the  serous 
coat  of  bowel,  peritoneum,  and  skin  together  to  prevent 
leakage  either  into  the  peritoneal  cavity  or  the  muscular 
layers,  when,  subsequently,  the  bowel  is  opened,  forming  an 
artificial  anus.  In  picking  up  a  portion  of  bowel  for  this 
operation,  it  should  be  remembered  that  large  intestine  is 
distinguished  from  small  intestine  not  merely  by  its  greater 
size  (which  is  variable)  and  thicker  walls,  but  also  by  the  longi- 
tudinal bands  and  the  appendices  epiploicae.  Sometimes  it  is 
necessary,  from  the  extent  of  disease  of  the  bowel  on  the  left 
side,  to  do  a  colotomy  on  the  right  side.  The  operation  is 
more  difficult,  the  caecum  not  coming  so  readily  into  the 
wound,  and  as  the  faecal  material  is  much  more  fluid  and  irri- 
tating at  this  point,  the  patient  has  difficulty  in  keeping  the 
parts  clean  and  the  skin  free  from  irritation.  In  connection 
with  the  statement  made  by  physiologists  that  the  large  intes- 
tine only  absorbs  water  and  some  salts,  it  is  important  to  note 
that  where  the  colon  is  opened  on  the  right  side  the  patient 
generally  emaciates  rapidly,  whereas,  when  opened  on  the  left, 
the  patient  may  rapidly  regain  an  excellent  bodily  condition. 

Dysenteric  ulcers  occur  generally  in  the  large  intestine,  par- 
ticularly toward  the  rectum  and  anus,  and  frequently  give  rise 
to  stricture. 

BLOOD-SUPPLY. — The  caecum  and  vermiform  appendix  are 
supplied  by  the  ileo-colic  ;  the  ascending  colon  by  the  right 
colic  ;  and  the  transverse  colon  by  the  middle  colic  of  the 
superior  mesenteric  ;  while  the  descending  colon  is  supplied  by 
the  left  colic,  and  the  iliac  and  pelvic  colon  by  the  sigmoid 
arteries  of  the  inferior  mesenteric.  The  rectum  is  supplied  by 
the  three  haemorrhoidal  arteries.  The  veins  present  similar 
arrangements. 

The  middle  colic  artery  supplying  the  transverse  colon  runs 
in  the  transverse  mesocolon  ;  and  in  performing  a  gastro- 
enterostomy,  in  which  the  mesocolon  is  perforated,  care  is 
necessary  to  avoid  injury  to  the  artery,  which  would  probably 
be  followed  by  gangrene  of  the  transverse  colon. 

The  NERVE-SUPPLY  is  derived  from  the  superior  mesenteric 
from  the  solar  plexus,  and  from  the  inferior  mesenteric  from 
the  aortic  plexus. 

The  LYMPHATICS  draining  the  bowel  from  caecum  to  upper 


THE  ABDOMEN  227 

portion  of  descending  colon  pass  to  the  mesocolic  glands, 
which  lie  behind  the  ascending  and  descending  colon,  between 
the  layers  of  the  transverse  mesocolon.  Those  draining  the 
lower  half  of  the  descending  colon,  and  iliac  and  pelvic  colons, 
join  the  left  lymphatic  trunk  of  the  lumbar  glands. 

The  LIVER  lies  under  the  diaphragm,  occupying  the  right 
and  central  portions  of  the  cavity  formed  by  that  dome- 
shaped  muscle  to  which  its  convex  parietal  surface  is  moulded, 
while  its  visceral  surface,  of  irregular  shape  and  moulded  to 
the  abdominal  viscera  upon  which  it  rests,  looks  down,  back- 
wards, and  to  the  left.  These  two  surfaces  meet  posteriorly 
in  a  curve,  while  anteriorly  they  meet  at  an  angle,  forming  the 
inferior  margin.  The  liver  varies  much  in  shape  and  size,  but 
its  normal  limits  in  health,  as  ascertained  by  percussion,  are  : 
Above,  from  a  point  i  inch  internal  to,  and  J  inch  below,  the 
right  nipple,  to  a  point  i  inch  below  the  left  nipple,  the  line 
dipping  between  these  points  to  cross  the  sternum  just  above 
the  gladiolar  xiphoid  junction.  The  right  border  corresponds 
to  a  curved  line  running  downwards  from  the  commencement 
of  the  line  marking  the  upper  limit  to  a  point  i  inch  below 
the  tip  of  the  tenth  costal  cartilage.  Commencing  from  this 
point,  the  lower  border  runs  to  the  left,  corresponding  with  the 
margin  of  the  ribs,  until  the  ninth  is  reached,  from  the  tip  of 
the  costal  cartilage  of  which  it  runs  in  a  curve,  with  the  con- 
vexity downwards,  reaching  midway  between  the  base  of  the 
ensiform  and  the  umbilicus,  till  it  reaches  the  tip  of  the  eighth 
costal  cartilage  on  the  left,  whence  it  runs  outwards  to  meet 
the  upper  border. 

The  inferior  margin  of  the  liver,  however,  is  thin,  and  overlaps 
the  stomach  and  intestine,  while  the  upper  border  is  overlapped 
by  the  base  of  the  right  lung,  and  hence  these  are  not  always 
easily  demarcated  by  percussion.  Further,  the  lower  border 
rises  and  falls  with  respiration,  and  also  descends  generally 
when  the  patient  assumes  the  upright  posture.  It  also  descends 
when  the  liver  is  enlarged,  as  from  tumour,  and  when  the  dia- 
phragm is  depressed,  as  in  emphysema.  Occasionally,  in 
multiparous  females  with  very  lax  abdominal  walls,  hepato- 
ptosis  may  occur,  the  liver  descending  to  the  level  of  the 
umbilicus,  or  even  the  right  inguinal  fossa.  In  some  cases, 
especially  of  tight-lacing,  the  lower  border  of  the  liver  may 
become  prominent,  and  even  present  a  projecting  process, 

15—2 


228  SURGICAL  ANATOMY 

called  RiedeVs  lobe,  which  may  be  mistaken  for  an  abdominal 
tumour.  On  the  other  hand,  the  upper  border  of  the  liver 
may  ascend,  pushing  the  diaphragm  and  lung  before  it,  the 
costo-diaphragmatic  recess  of  the  pleura  becoming  deepened, 
and  the  diaphragm  lying  in  contact  with  the  thoracic  wall 
over  a  larger  area.  In  such  cases  the  liver  may  be  opened 
through  the  chest  wall,  pleural  sac,  and  diaphragm  (trans- 
pleural  hepatotomy).  The  left  border  also  varies  in  position, 
sometimes  extending  right  across  to  the  left  lateral  abdominal 
wall.  The  liver  is  divided  into  two  lobes,  right  and  left,  by  the 
falciform  ligament.  It  has  an  intimate  fibrous-tissue  covering, 
which  is  most  abundant  where  the  serous  coat  is  absent,  and 
particularly  so  at  the  portal  fissure,  where  it  is  known  as 
Glissons  capsule,  and  surrounds  the  vessels  entering  the 
fissure,  and  accompanies  them  into  the  liver  substance.  It  is 
entirely  covered  with  peritoneum,  save  for  a  space  on  the  pos- 
terior surface  of  the  right  lobe,  which  corresponds  to  the  in- 
terval between  the  two  layers  of  the  coronary  ligament,  and  is 
attached  directly  to  the  diaphragm  by  areolar  tissue,  through 
which  the  portal  circulation  of  the  liver  communicates  with 
the  systemic  circulation  in  the  diaphragm.  The  left  margin 
of  the  uncovered  area  is  marked  below  by  the  suprarenal 
capsule  of  the  right  kidney,  and  immediately  to  the  left  of  this 
is  the  deep  groove  through  which  the  vena  cava  passes,  this 
groove  being  sometimes  converted  into  an  actual  tunnel  by 
overlapping  of  the  uncovered  area  on  the  right,  and  the 
Spigelian  lobe  on  the  left. 

The  left  margin  of  the  Spigelian  lobe,  in  turn,  is  grooved  by 
the  fissure  of  the  ductus  venosus,  which  at  this  part  separates 
the  right  lobe  from  the  left  lobe  ;  and  immediately  to  the  left 
of  it  is  the  cesophageal  groove,  which  leads  down  to  the  gastric 
impression  on  the  visceral  surface.  The  VISCERAL  SURFACE 
of  the  left  lobe  rests  upon  the  upper  surface  and  lesser  curva- 
ture of  the  stomach,  which  produces  the  gastric  impression, 
while  that  of  the  right  lobe  is  divided  into  two  by  the  gall- 
bladder lying  antero-posteriorly.  To  the  right  of  the  gall- 
bladder the  visceral  surface  is  marked  by  the  colic  impression 
in  front  and  the  renal  impression  behind,  and  the  duodenal 
impression  between  the  two  and  the  gall-bladder.  To  the  left 
of  the  gall-bladder,  and  between  it  and  the  falciform  ligament, 
are,  from  before  backwards,  (i)  the  quadratic  lobe,  resting  upon 


THE  ABDOMEN 


229 


the  pylorus  or  the  beginning  of  the  duodenum  ;  (2)  the  portal 
fissure,  through  which  the  portal  vein,  hepatic  artery,  and 
hepatic  duct  enter  the  liver,  the  two  layers  of  the  lesser 
omentum  tying  attached  to  its  borders ;  (3)  caudate  lobe  (lying 
between  the  portal  fissure  and  vena  cava),  which  is  small,  and 
rests  on  the  foramen  of  Winslow.  The  INFERIOR  MARGIN  of 
the  liver  presents  a  notch  (umbilical)  at  the  attachment  of  the 


17 


15 


12       11     109  8  7 

FIG.  28.— THE  INFERIOR  SURFACE  OF  THE  LIVER. 
(From  Buchanan's  "Anatomy.") 


1.  Lobus  caudatus. 

2.  Impressio  suprarenalis. 

3.  Uncovered  area  of  right  lobe. 

4.  Impressio  duodenalis. 

5.  Impressio  renalis. 

6.  Cystic  duct. 

7.  Impressio  colica. 

8.  Gall-bladder. 

9.  Lobus  quadratus. 

10.  Ductus  communis  choledochus. 


IT.  Round  ligament. 

12.  Hepatic  duct. 

13.  Hepatic  artery. 

14.  Tuber  omentale. 

15.  Impressio  gastric  on  left  lobe. 

1 6.  Vena  portae. 

17.  CEsophageal  groove. 

1 8.  Venosal  fissure. 

19.  Lobus  Spigelii. 

20.  Inferior  vena  cava. 


round  ligament.  It  is  situated  ij  inches  to  the  right  of  the 
middle  line.  The  notch  marks  the  commencement  of  the 
LONGITUDINAL  FISSURE  of  the  liver,  which  divides  the  liver  into 
right  and  left  lobes,  and  which  is  composed  anteriorly  of  the 
umbilical  fissure,  and  posteriorly  of  the  fissure  of  the  ductus 
venosus.  The  deep  umbilical  fissure,  lodging  the  round  liga- 
ment, runs  into  the  left  extremity  of  the  portal  fissure,  beyond 


23o  SURGICAL  ANATOMY 

which  point  the  separation  into  right  and  left  lobes  is  con- 
tinued by  the  fissure  of  the  ductus  venosus,  which  converges 
above  to  meet  the  fissure  of  the  vena  cava,  and  lodges  the 
fibrous  remains  of  the  ductus  venosus.  The  round  ligament 
is  the  remains  of  the  left  umbilical  vein  (the  right  one  disap- 
pearing altogether  at  an  early  stage),  which  runs  from  the 
umbilicus  to  the  left  branch  of  the  portal  vein.  Like  the 
round  ligament,  the  ductus  venosus  is  a  foetal  channel,  and 
carries  blood  from  the  left  branch  of  the  portal  vein  to  the 
vena  cava  direct,  without  going  into  the  liver.  It  becomes 
obliterated  at  birth,  and  degenerates  into  a  fibrous  cord. 
Thus,  round  ligament  (or  umbilical  vein)  and  ductus  venosus 
in  the  foetus  are  practically  continuous  structures,  blood 
passing  direct  from  the  placenta  along  the  umbilical  vein 
through  the  ductus  venosus  to  the  inferior  vena  cava,  and 
so  to  the  heart  direct. 

The  fossa  lodging  the  gall-bladder  is  usually  devoid  of  peri- 
toneum, the  gall-bladder  lying,  as  a  rule,  directly  in  contact 
with  the  liver  (sometimes,  however,  it  is  suspended  by  a  short 
mesentery),  and  situated  at  a  point  where  the  right  Poupart 
line  crosses  the  lower  margin  of  the  ribs  (between  rib  margin 
and  outer  border  of  rectus).  With  the  exception  of  the  un- 
covered area,  the  gall-bladder  fossa  just  mentioned,  and  a 
small  area  between  the  layers  of  the  falciform  ligament,  the 
whole  organ  is  invested  with  peritoneum,  all  derived  from  the 
great  sac,  except  that  covering  the  caudate  and  Spigelian 
lobes. 

The  liver  is  maintained  in  position  by  its  adhesion  to 
the  under-surface  of  the  diaphragm  at  the  uncovered  area  ; 
by  the  two  coronary  ligaments  which  are  peritoneal  processes 
reflected  from  its  margin  on  to  the  diaphragm  ;  the  left  lateral 
ligament  running  from  the  left  lobe  to  the  diaphragm,  and 
the  falciform  ligament  (both  peritoneal)  ;  its  attachments  to 
the  vena  cava ;  and  the  upward  pressure  of  other  abdominal 
organs.  The  falciform  ligament  consists  of  a  crescentic  double 
layer  of  peritoneum,  whose  convex  border  is  attached  to  the 
under  surface  of  the  diaphragm  and  anterior  abdominal  wall, 
about  i  inch  to  the  right  of  the  middle  line  ;  while  the  concave 
border,  free,  and  containing  the  round  ligament,  extends  from 
close  to  the  umbilicus  to  the  umbilical  notch  of  the  liver.  The 
gastro-hepatic  omentum,  extending  from  the  liver  to  the  lesser 


THE  ABDOMEN  231 

curvature  of  the  stomach,  consists  of  two  folds  of  peritoneum — 
the  anterior,  derived  from  the  greater  sac  ;  and  the  posterior, 
from  the  lesser  sac — between  which,  at  its  right  extremity, 
are  the  bile-duct,  hepatic  artery,  and  portal  vein,  with  nerves 
and  lymphatics.  Notwithstanding  its  attachments,  however, 
the  liver  has  occasionally  descended  to  the  level  of  the  um- 
bilicus, or  even  into  the  iliac  fossa  (ptosis  of  the  liver),  the 
organ  turning  in  its  descent,  so  that  its  diaphragmatic  surface 
becomes  anterior. 

Vessels. — The  PORTAL  VEIN,  formed  by  the  junction  of 
the  superior  mesenteric  and  splenic  veins,  commences  behind 
the  head  of  the  pancreas,  ascends  behind  the  first  part  of  the 
duodenum,  and  then,  accompanied  by  the  bile-duct  and 
hepatic  artery,  proceeds  between  the  layers  of  the  gastro- 
hepatic  omentum  to  the  transverse  fissure,  where  it  divides 
into  right  and  left  branches,  of  which  the  latter  is  connected 
with  the  round  ligament  and  ductus  venosus.  The  portal 
vein  conveys  blood  from  the  stomach,  intestines  (excepting 
lower  portion  of  rectum),  spleen,  and  pancreas,  and  ramifies 
in  the  substance  of  the  liver. 

Portal  obstruction  may  arise  from  pressure  on  the  veins, 
from  tumours  of  the  head  of  the  pancreas  or  adjacent  parts, 
from  cirrhosis  or  tumours  of  the  liver  itself,  or  from  valvular 
disease  of  the  heart  (causing  engorgement  and  '  nutmeg 
liver').  In  such  cases  abdominal  ascites  generally  occurs, 
the  abdominal  cavity  becoming  distended  with  free  fluid. 
The  circulation  is  so  far  relieved  by  (i)  para-umbilical  com- 
munication between  veins  of  the  abdominal  wall  and  portal  ; 
(2)  communication  of  portal  and  systemic  veins  at  uncovered 
surface  of  liver  ;  (3)  similar  communication  between  veins  of 
the  lower  part  of  the  oesophagus  and  those  of  the  stomach  ; 
(4)  similar  communication  between  the  superior  (portal)  with 
the  middle  and  inferior  haemorrhoidal  (systemic).  In  order 
to  assist  the  circulation,  an  artificial  anastomosis  between 
portal  and  systemic  venous  systems  has  been  made  by  bringing 
a  portion  of  great  omentum  into  contact  with  the  subcutaneous 
tissues  of  the  abdominal  wall.  Hemorrhoids  frequently  occur 
in  portal  congestion. 

The  HEPATIC  ARTERY  arises  from  the  cceliac  axis,  runs 
along  the  upper  border  of  the  pancreas,  giving  off  pan- 
creatic, pyloric,  and  gastro-duodenal  branches,  enters  the 


232  SURGICAL  ANATOMY 

gastro-hepatic  omen  turn,  and  so  reaches  the  transverse 
fissure.  It  divides  into  right  and  left  branches,  the  cystic 
artery  being  given  off  from  the  right  division,  which  ramifies 
in  the  portal  canals.  The  blood  is  conveyed  from  the 
liver  to  the  inferior  vena  cava  by  the  hepatic  veins.  The 
portal  vein,  hepatic  artery,  and  bile-ducts  are  surrounded  by 
connective  tissue  derived  from  the  connective  tissue  which 
invests  the  surface  of  the  liver,  and  is  known  as  Glisson's 
capsule.  Thus,  these  structures  may  collapse  when  cut, 
whereas  the  hepatic  veins  are  embedded  in  liver  tissue,  and 
hence  gape  when  cut,  and,  as  they  have  no  valves,  ma}^  re- 
gurgitate blood  from  the  inferior  vena  cava.  This  point  is  of 
importance  in  relation  to  injury  of  the  liver,  which  is  fre- 
quently ruptured  from  blows  or  crushes.  If  the  capsule  be 
torn,  the  patient  may  die  from  haemorrhage,  whereas  if  it 
remain  intact,  as  not  infrequently  occurs,  the  patient  may 
recover.  Considerable  portions  of  liver  have  been  removed, 
however,  by  ligature,  incision  by  cautery,  and  even  by  excision 
by  knife,  with  success  (hepatectomy) ,  and  in  this  connection 
it  should  be  remembered  that  the  blood-pressure  in  the  liver 
is  low.  The  liver  is  occasionally  damaged  by  fractured  ribs, 
and  even  extensive  wounds  of  the  liver  may  be  recovered 
from.  The  liver  very  frequently  becomes  secondarily  affected 
by  carcinoma,  many  nodules  forming,  some  of  which  may  be 
easily  palpated  as  they  lie  on  the  surface,  while  the  organ 
becomes  greatly  enlarged.  The  infection  of  the  liver  is  gene- 
rally comparatively  early  in  carcinoma  of  the  stomach,  from 
which  the  infection  is  believed  to  be  conveyed  by  the  portal 
vein  (as  is  likewise  conveyed  infection  from  carcinoma  recti). 

The  LYMPHATICS  of  the  liver  are  arranged  in  two  sets — 
superficial  and  deep.  The  former  lie  under  the  peritoneal 
covering,  and  drain  to  the  hepatic  glands  in  the  lesser  omen- 
turn,  lumbar,  anterior  mediastinal  glands,  and  right  lymphatic 
duct.  The  latter  accompany  the  hepatic  and  portal  veins, 
and  drain  to  the  hepatic  glands  and  to  the  thoracic  duct. 
The  NERVES  are  derived  from  the  left  pneumogastric  and 
solar  plexus. 

The  liver  is  not  infrequently  the  seat  of  abscesses.  These 
may  occur  in  connection  with  pycemia,  when  they  are  small, 
multiple,  and  superficial ;  or  from  ulcerative  conditions  of  the 
bowel  (the  infection  probably  being  conveyed  by  the  portal 


THE  ABDOMEN  233 

vein)  or  biliary  passages,  when  the  abscess  is  generally  large, 
single,  and  deeply  seated.  The  pyaemic  multiple  abscesses 
occur  frequently  in  connection  with  pyogenic  head  affections — 
as,  for  example,  suppurative  sigmoid  sinus  thrombosis — but 
are  rare  in  pyaemia  from  urinary  affections  or  burns.  '  Tropical 
abscess,'  which  occurs  in  connection  with  dysentery,  is  a  good 
example  of  the  solitary  type.  While  at  first  deeply  seated, 
the  abscess  may  progress  either  upwards  towards  the  dia- 
phragm or  down  toward  the  peritoneum.  In  the  first  case,  it 
gives  rise  to  cough  from  irritation  of  the  vagus  filaments  in  the 
liver,  and  to  pain  in  the  right  shoulder  region  from  irritation 
of  the  right  phrenic  (both  in  the  liver  and  the  diaphragm), 
which  communicates  with  the  superficial  descending  cutaneous 
branches  of  the  cervical  plexus.  The  abscess  may  burst  into 
the  pleura,  but,  more  generally,  from  soldering  of  its  layers, 
bursts  into  the  lung,  and  may  be  coughed  up  through  the 
bronchi,  or  may  cause  suffocation.  Where  the  abscess  pro- 
ceeds downwards,  it  may  burst  into  the  stomach,  intestine,  or 
peritoneal  cavity.  The  abscess  may  be  attacked  through  the 
abdomen  (generally  in  two  stages,  to  permit  of  soldering  of 
the  peritoneum  round  the  wound,  thus  shutting  off  the  peri- 
toneum), or  by  the  transpleural  route. 

The  liver  is  the  most  common  seat  of  hydatid  cysts,  the 
embryo  boring  its  way  from  the  intestine  into  the  portal 
vein,  and  being  thus  conveyed  to  the  liver.  Such  cysts 
may  attain  a  large  size,  and  sometimes  burst  into  the 
lungs.  They  may  be  attacked  by  either  of  the  routes 
mentioned  for  abscess.  The  large  bile-ducts  which  converge 
to  the  transverse  fissure,  to  form  by  their  junction  the 
right  and  left  hepatic  ducts,  present  numerous  dilatations, 
which  may  act  as  reservoirs  when  the  gall-bladder  has  been 
removed  or  rendered  insufficient.  The  two  hepatic  ducts  join 
to  form  the  hepatic  duct,  which  runs  downwards  for  I  inch 
in  the  portal  fissure  to  the  point  where,  joined  by  the  cystic 
duct,  it  forms  the  common  bile-duct. 

The  gall-bladder  is  a  thin- walled,  pyriform  sac,  about 
3  inches  long,  lying  obliquely  on  the  under-surface  of  the  liver, 
to  which  it  is  attached  by  connective  tissue.  Below,  it  is  in 
contact  with  the  transverse  colon  in  front,  and  duodenum 
behind.  It  is  invested  with  peritoneum,  except,  as  a  rule,  on 
its  upper  surface.  Its  Hindus  is  directed  downwards,  forwards, 


234  SURGICAL  ANATOMY 

and  to  the  right,  and  when  the  bladder  is  full  presents  in  the 
angle  between  the  outer  border  of  the  rectus  and  the  costal 
margin,  opposite  the  ninth  cartilage.  The  neck  presents  an 
S-shaped  curve  (and  presents  internally  a  somewhat  spiral 
folding  of  the  mucous  membrane,  which  is  said  to  obstruct  the 
passage  of  gall-stones),  and  ends  in  the  cystic  duct,  which  is 
slightly  narrower  and  longer  than  the  hepatic  duct  which  it 
runs  backwards  and  inwards  to  meet.  The  two  ducts  join  at 
the  mouth  of  the  portal  fissure  to  form  the  COMMON  BILE-DUCT, 
which,  about  2  inches  long,  runs  down  in  front  of  the  foramen 
of  Winslow,  between  the  layers  of  the  lesser  omen  turn,  with 
the  portal  vein  behind  and  the  hepatic  artery  to  the  left. 
It  now  descends  behind  the  first  part  of  the  duodenum,  and 
then  between  the  pancreas  and  second  portion  of  the  duo- 
denum, where  it  meets  the  pancreatic  duct,  along  with  which  it 
runs  obliquely  through  the  duodenal  wall,  to  open  on  a  common 
papilla  4  inches  beyond  the  pylorus.  The  gall-bladder  is  not 
infrequently  distended,  sometimes  from  the  impaction  of  a 
stone  in  the  cystic  duct,  or  an  accumulation  of  stones  in  the 
bladder  itself,  or  from  obstruction  in  the  common  bile-duct, 
by  malignant  growths  of  the  duodenum,  pancreas,  etc.  Where 
greatly  distended,  it  has  been  mistaken  for  an  ovarian  cyst, 
the  mass  extending  below  the  umbilicus.  While  at  first  the 
bladder  is  distended  with  bile,  in  long-standing  cases,  where 
the  duct  becomes  occluded,  it  may  only  contain  clear  fluid. 
It  also  sometimes  contains  pus.  The  irritative  process  extends 
through  the  walls  of  the  bladder  to  the  surrounding  structures, 
and  thus  the  bladder  may  contract  adhesion  to  the  duodenum, 
colon,  etc.  In  some  cases  where  a  large  stone  has  been  lodged 
in  the  gall-bladder,  and  such  adhesions  have  formed,  the  stone 
has  ultimately  ulcerated  its  way  through  into  the  duodenum, 
and  become  impacted  in  the  ileum,  causing  intestinal  obstruc- 
tion. In  other  cases  it  has  ulcerated  its  way  through  the 
anterior  abdominal  parietes.  In  operating  on  the  gall-bladder, 
an  incision  is  made  either  vertically  through  the  rectus  or  right 
semilunar  line,  or  obliquely  beneath  the  costal  margin,  and 
the  bladder  and  ducts  exposed  and  examined. 

For  the  removal  of  stones  in  the  bladder  after  aspiration  of 
fluid  contents,  cholecystotomy  may  be  performed,  the  bladder 
being  subsequently  closed  by  stitching  ;  or  a  cholecystostomy, 
in  which  the  opened  bladder  is  stitched  to  the  abdominal 


THE  ABDOMEN  235 

wound,  and  allowed  to  heal  by  granulations.  Choledochotomy 
is  the  operation  for  removal  of  a  calculus  in  the  common  bile- 
duct  by  longitudinal  incision,  which  is  subsequently  stitched 
(the  part  being  surrounded  by  gauze  packing,  as  leakage  is 
common).  One  or  two  lymphatic  glands  lie  in  the  gastro- 
hepatic  omentum  close  to  the  neck  of  the  gall-bladder,  which, 
when  enlarged  or  calcined,  may  be  mistaken  for  gall-stones. 
Where  the  stone  is  lodged  in  the  lower  extremity  of  the 
common  bile-duct  (ampulla of  Voter),  it  maybe  expressed  into 
the  duodenum  or  crushed.  If  a  cutting  operation  be  necessary, 
difficulty  is  experienced,  the  pancreas  or  duodenum  frequently 
requiring  to  be  cut  into.  Cholecystectomy ,  or  removal  of  the 
gall-bladder  by  stripping  the  peritoneum  and  ligaturing  the 
neck  and  cystic  artery,  may  be  performed  for  new  growths, 
occlusion  of  the  duct,  etc.  Cholecyst  enter ostomy  consists  in 
joining  the  gall-bladder  and  duodenum  so  as  to  make  a  fistula 
in  cases  where  the  common  bile-duct  is  obstructed.  The 
nerve-supply  of  the  gall-bladder  is  from  the  eighth  and  ninth 
segments  of  the  cord  through  the  great  splanchnic  and  cceliac 
plexus  ;  and  hence  in  passage  of  gall-stones  pain  may  be 
referred  to  the  parietes  over  the  epigastrium,  right  hypo- 
chondrium,  and  lumbar  region  (biliary  colic). 

The  PANCREAS,  about  6  inches  long,  runs  almost  horizon- 
tally across  the  abdomen  at  the  level  of  the  first  lumbar  ver- 
tebra, about  3  inches  above  the  umbilicus.  The  tail  is  in 
contact  with  the  spleen  ;  the  body  is  prismatic  in  shape,  one 
edge  pointing  anteriorly  ;  while  at  the  attenuated  neck  the 
organ  describes  a  semicircle,  so  that  the  head  is  directed  down- 
wards and  to  the  left,  being  lodged  in  the  concavity  formed  by 
the  loop  of  the  duodenum.  In  front  the  head  is  in  relation  to 
the  transverse  colon,  and  behind  to  the  vena  cava,  renal 
vessels,  and  aorta.  The  uncinate  process  of  the  head  is  some- 
times separate,  forming  the  lesser  pancreas.  The  neck  is 
narrow,  lies  in  front  of  the  portal  vein,  and  presents  a  notch  on 
the  left  side  at  its  junction  with  the  head,  through  which  the 
superior  mesenteric  vessels  pass,  separating  the  head  and 
neck  from  the  duodeno-jejunal  flexure.  The  posterior  surface 
of  the  body  has  no  peritoneal  covering,  but  is  attached  by 
areolar  tissue  to  the  posterior  abdominal  wall  and  the  organs 
lying  on  it — namely,  aorta,  and  origin  of  superior  mesenteric 
artery,  left  renal  vessels,  left  suprarenal  capsule,  and  left 


236  SURGICAL  ANATOMY 

kidney.  The  splenic  artery  (with  the  vein  below  it)  runs 
behind  the  upper  border  of  the  pancreas.  The  upper  surface 
of  the  body  presents  a  small  projection,  the  tuber  omentale,  at 
its  junction  with  the  neck.  This  upper  surface  is  covered  by 
the  posterior  layer  of  .the  lesser  peritoneal  sac,  which  separates 
it  from  the  stomach  which  rests  on  it.  The  inferior  surface 
is  covered  by  descending  peritoneum  derived  from  the  trans- 
verse mesocolon,  and  is  in  contact  with  the  duodeno-jejunal 
flexure,  small  intestine,  and  splenic  flexure  of  the  colon.  The 
pancreatic  duct  (of  Wirsung)  runs  almost  from  the  tail  forward, 
till,  on  reaching  the  neck,  it  meets  the  bile-duct  and  opens,  as 
already  described,  about  4  inches  beyond  the  pylorus.  It 
receives  many  branches  in  its  course,  and  frequently  an 
accessory  duct  (of  Santorini)  opens  into  the  duodenum  f-  inch 
above  the  main  duct,  with  which  it  previously  anastomoses. 
The  blood-supply  is  derived  from  the  superior  and  inferior 
pancreatico-duodenal  arteries  (from  the  gastro-duodenal  and 
superior  mesenteric  respectively),  inferior  pancreatic  (from 
either  gastro-duodenal  or  superior  mesenteric),  and  branches 
from  splenic  and  hepatic  arteries.  The  veins  open  into  the 
superior  mesenteric,  portal,  and  splenic  veins.  The  lymphatics 
pass  to  the  cceliac  glands,  and  the  nerves  are  derived  from  the 
solar  plexus,  through  the  superior  mesenteric,  cceliac,  and 
splenic  plexuses. 

In  addition  to  secreting  the  pancreatic  juice  for  digestion  of 
carbohydrates,  the  pancreas  is  supposed  to  supply  an  '  in- 
ternal secretion,'  the  destruction  of  the  pancreas  by  disease 
giving  rise  to  pancreatic  diabetes.  Owing  to  its  impor- 
tant functions,  obscurity  of  its  pathological  phenomena,  and 
to  its  difficult  position,  the  pancreas  has  not  been  much  sub- 
jected to  surgical  interference.  Recently  attention  has  fre- 
quently been  called  to  pancreatitis,  sometimes  giving  rise  to 
suppuration,  and  necessitating  surgical  interference  to  prevent 
peritonitis.  Pancreatic  cysts  occasionally  arise  from  obstruc- 
tion of  the  duct,  from  a  calculus  or  pressure  on  it  from  without. 
The  cyst  generally  commences  in  the  tail,  and  as  it  increases 
in  size  presents  between  stomach  and  transverse  colon,  push- 
ing the  great  omentum  before  it.  Such  cysts  sometimes 
attain  a  very  large  size.  Both  cysts  and  abscesses  are  gene- 
rally best  reached  by  a  median  incision  above  the  umbilicus, 
and  then  opening  through  the  omentum.  Carcinoma  not  in- 


THE  ABDOMEN  237 

frequently  occurs  in  the  head,  rapidly  involving  the  pancreatic 
and  bile  ducts,  and  pressing  on  the  portal  vein,  pylorus,  and 
other  surrounding  parts.  Removal  by  operation  is  generally 
out  of  the  question.  Rarely  it  has  been  found  in  a  diaphrag- 
matic hernia,  or  sloughed  off  after  having  been  invaginated 
into  the  sac.  Attempts  have  been  made  in  cases  of  pancreatic 
diabetes  to  implant  portions  of  healthy  pancreatic  tissue  in 
the  subcutaneous  tissues. 

The  SPLEEN  is  about  5  inches  long  and  3  inches  broad.  It 
may  be  compared  in  shape  to  a  thick  pancake,  which,  instead 
of  being  circular,  is  roughly  triangular  in  outline,  while  its 
visceral  surface  presents  marked  indentations  caused  by  pres- 
sure of  adjacent  organs.  It  is  placed  far  back  in  the  upper 
portion  of  the  abdominal  cavity,  its  long  axis  corresponding 
in  direction  to  the  posterior  portion  of  the  tenth  rib,  while  its 
parietal  surface  is  moulded  to  the  back  part  of  the  diaphragm, 
by  which,  together  with  pleura  and  thin  basal  margin  of  lung, 
it  is  separated  from  the  ninth,  tenth,  and  eleventh  ribs.  The 
apex  reaches  a  point  i  inch  from  the  spine.  The  anterior  basal 
angle  is  the  most  anterior  part,  but  does  not  present  normally 
beyond  the  costal  margin.  The  notch  of  the  spleen  lies  above 
this  angle  on  the  anterior  margin.  The  visceral  surface  pre- 
sents three  impressions — anterior,  posterior,  and  inferior. 
Anteriorly  a  deep  concavity  corresponds  to  the  fundus  of  the 
stomach,  arid  near  the  posterior  part  of  this  depression  is  the 
hilum  at  which  the  vessels  enter.  Behind  the  gastric  depres- 
sion is  the  renal  depression,  formed  by  the  anterior  surface 
of  the  kidney  ;  while  lying  under  these  two  is  the  intestinal  im- 
pression, formed  by  the  splenic  flexure  of  the  colon.  In  the 
neighbourhood  of  -the  spleen  accessory  masses  of  splenic  tissue 
are  not  infrequently  found  (lienculi).  The  spleen  is  almost 
enveloped  in  peritoneum,  the  peritoneum  passing  from  the 
hilum  to  the  anterior  surface  of  the  kidney,  forming  the  lieno- 
renal  ligament ;  and  to  the  fundus  of  the  stomach,  forming  the 
gastro-splenic  omentum.  Under  the  peritoneal  covering  the 
spleen  possesses  a  tough  fibrous  capsule,  containing  both  elastic 
and  involuntary  muscular  fibres.  While  distensible,  this 
capsule  is  also  contractile,  and  may  account  for  arrest  of 
haemorrhage  in  punctured  or  gunshot  wounds  of  the  spleen. 
The  blood  is  conveyed  by  the  splenic  artery,  the  largest  branch 
of  the  cceliac  axis,  which  runs  along  the  upper  border  of  the 


238  SURGICAL  ANATOMY 

pancreas ;  passes  between  the  layers  of  the  lieno-renal  liga- 
ment ;  breaks  up  into  several  branches,  and  so  enters  the  hilus 
after  supplying  branches  to  the  stomach.  The  splenic  vein 
joins  the  superior  mesenteric  behind  the  head  of  the  pancreas 
to  form  the  portal  vein. 

The  nerve-supply  is  the  splenic  plexus,  derived  from  the 
coeliac  of  the  solar  plexus.  There  are  no  lymphatics  in  the 
spleen,  but  some  are  present  in  the  capsule.  The  normal 
position  of  the  spleen  is  indicated  by  a  line  running  obliquely 
downwards  and  forwards  from  a  point  i  J  inches  in  front  of  the 
ninth  dorsal  spine  to  a  point  on  the  tenth  rib  at  the  level  of  the 
first  lumbar  spine,  encircled  by  an  oval  3  inches  in  transverse 
diameter.  Owing  to  the  intervention  of  the  lung  between 
the  spleen  and  chest  wall,  it  is  practically  impossible  to  outline 
its  limits.  Normally,  the  spleen  does  not  project  beyond  the 
ribs,  but,  when  enlarged,  the  anterior  basal  angle  projects,  and 
then  it  is  generally  possible  to  detect  one  or  more  notches  on 
the  anterior  border,  which  serve  to  distinguish  splenic  from 
other  enlargements  in  the  same  region. 

Pathological  enlargement  of  the  spleen  is  seen  in  various 
fevers,  and  chronically  in  leucocythaemia,  Hodgkin's  disease, 
malaria  (ague  cake),  etc.  In  the  latter  the  organ  is  extremely 
easily  ruptured,  fatal  haemorrhage  frequently  following  the 
accident.  In  some  cases  the  enlargement  is  enormous, 
the  spleen  occupying  the  greater  part  of  the  abdomen. 
The  spleen  may  be  punctured  by  fractured  ribs,  but  not 
infrequently  the  spleen  is  ruptured,  whereas,  owing  to 
their  elasticity,  the  ribs  escape  fracture.  As  the  spleen 
is  very  vascular,  enormous  hemorrhage  generally  occurs, 
the  abdomen  being  filled  with  blood,  and  death  gene- 
rally resulting.  In  some  cases,  however,  the  ruptured  spleen 
has  been  removed,  and  the  bleeding  vessels  ligatured,  with 
excellent  results.  As  the  splenic  artery  is  an  end  artery, 
infarctions  not  infrequently  occur  in  the  spleen,  from  emboli 
being  lodged,  and  if  these  are  septic,  abscesses  may  arise. 
These  are  generally  multiple  and  peripheral.  A  large  single 
abscess  of  the  spleen  is  rare.  Particularly  in  females,  and 
associated  with  general  displacement  of  the  viscera,  the  spleen 
may  be  found  displaced,  and  possessing  an  elongated  pedicle, 
which  permits  of  considerable  movement,  the  spleen  some- 
times reaching  the  pelvis  (wandering  spleen).  In  such  cases 


THE  ABDOMEN  239 

the  spleen  may  be  restored  and  fixed  by  sutures  (splenopexy) , 
or  may  be  removed  (splenect 


LUMBAR  REGION. 

The  lumbar  region  extends  from  the  level  of  the  twelfth 
dorsal  vertebra  and  twelfth  rib  to  the  base  of  the  sacrum, 
ilio-lumbar  ligament,  and  iliac  crest.  Externally  it  is  limited 
on  the  posterior  aspect  by  the  outer  border  of  the  erector  spinae, 
indicated  by  a  vertical  furrow  running  between  it  and  the  flat 
abdominal  muscles,  while  on  the  abdominal  surface  it  is  limited 
by  the  outer  border  of  the  quadratus  lumborum,  the  latter 
muscle,  together  with  the  psoas,  forming  the  floor  of  the  space. 

The  iliac  fossa  is  bounded  above  by  the  ilio-lumbar  liga- 
ment, and  above  and  externally  by  the  crest  of  the  ilium, 
internally  by  the  brim  of  the  true  pelvis,  and  in  front  by 
Poupart's  ligament.  It  lodges  the  iliacus  muscle,  which, 
blending  with  the  psoas  to  form  the  ilio-psoas,  runs  down  to 
the  small  trochanter  of  the  femur.  The  FASCIAL  COVERINGS 
of  these  muscles,  and  particularly  of  the  psoas,  are  of  con- 
siderable importance  surgically. 

Three  layers  of  fascia  run  outwards  from  the  vertebrae,  and 
fuse,  enclosing  muscles  as  they  do  so,  to  form  the  lumbar 
aponeurosis.  The  most  posterior  of  these  three  fasciae,  called 
the  vertebral  aponeurosis,  extends  outwards  from  the  spines  of 
the  vertebrae  to  meet  the  middle  layer,  which  arises  from  the  tips 
of  the  transverse  processes  of  the  lumbar  vertebrae,  enclosing 
the  erector  spinae  between  them.  The  anterior  layer  arises  from 
the  junctions  of  transverse  processes  and  bodies,  and  extends 
outwards  to  meet  the  midolJe  layer,  enclosing  the  quadratus 
lumborum,  and  separating  it  anteriorly  from  the  psoas  (see 
Fig.  19). 

The  PSOAS  FASCIA,  OR  SHEATH,  forms  a  fourth  layer,  which, 
rising  from  the  front  of  the  bodies  of  the  lumbar  vertebra  (with 
arches  to  permit  of  the  passing  of  the  lumbar  arteries),  runs 
outwards  and  fuses  with  the  anterior  layer,  shortly  before  it 
fuses  with  the  middle  and  posterior  layers  to  form  the  lumbar 
aponeurosis.  Above,  the  psoas  sheath  commences  at  the 
internal  arcuate  ligament  of  the  diaphragm,  being  derived 
from  the  diaphragmatic  portion  of  the  transversalis  fascia, 
and  thus  the  psoas  muscle  only  receives  its  sheath  after 
perforating  the  diaphragm. 


240  SURGICAL  ANATOMY 

The  LUMBAR  APONEUROSIS  is  a  narrow  ligamentous  band, 
extending  from  the  last  rib  to  the  iliac  crest.  Besides 
giving  attachments  to  the  internal  oblique  and  transver- 
salis  muscles,  it  is  continuous  by  its  anterior  edge  with 
the  transversalis  fascia,  and  hence  it  connects  the  outer 
border  of  the  psoas  sheath  with  the  inner  border  of  the 
transversalis  fascia.  It  is  pierced  near  the  rib  by  the 
last  intercostal  artery  and  nerve,  and  near  the  ilium 
by  the  ilio-hypogastric  nerve  and  accompanying  artery. 
The  FASCIAE  LINING  THE  ABDOMINAL  CAVITY  in  the  lumbar 
region  are  the  transversalis,  lining  the  antero-lateral  por- 
tion, the  anterior  layer  of  lumbar  fascia,  and  psoas  sheath 
completing  the  investment.  The  three  layers  forming  the 
lumbar  aponeurosis  are,  like  it,  inserted  below  into  the  crest 
of  the  ilium,  the  lower  margin  of  the  anterior  layer  being 
thickened  to  form  the  ilio-lumbar  ligament,  which  extends 
from  the  transverse  process  of  the  last  lumbar  vertebra  to 
the  inner  lip  of  the  iliac  crest  (while  its  upper  margin  forms 
the  external  arcuate  ligament).  The  psoas  sheath,  however, 
on  reaching  the  iliac  fossa,  becomes  directly  continuous  with 
the  ILIAC  FASCIA,  covering  the  iliacus  muscle,  and  thus  it  is 
necessary  to  consider  these  two  together  in  that  region.  This 
iliac  fascia,  then,  is  attached  along  the  whole  iliac  crest  and 
ilio-lumbar  ligament.  Then  it  extends  over  the  psoas,  on 
the  inner  border  of  which  it  is  attached  to  the  sacrum  and 
brim  of  the  true  pelvis,  and  ilio-pectineal  eminence,  and  is 
continuous  with  the  pelvic  fascia.  Along  Poupart's  ligament 
it  fuses  with  the  transversalis  fascia,  save  where  the  external 
iliac  vessels  emerge  to  form  the  femoral  vessels,  the  trans- 
versalis fascia  at  this  point  joining  in  front  of,  and  the  iliac 
fascia  behind,  the  vessels,  to  form  their  sheath  (femoral  sheath) . 
Thus  the  ilio-psoas  muscle  and  anterior  crural  nerve  enter 
the  thigh  through  a  compartment  composed  of  fascia  and  bone, 
which  is  closed,  save  for  the  communication  with  the  psoas 
above,  and  with  the  pelvis  below  and  to  the  inside.  Under  the 
iliac  fascia  the  external  iliac,  by  its  circumflex  iliac  branch, 
anastomoses  with  the  ilio-lumbar  branch  of  the  internal  iliac. 

The  INTERNAL  SURFACE  of  the  abdominal  cavity,  then, 
is  lined  by  a  continuous  fascial  covering,  variously  named 
at  different  parts,  the  chief  portions  being  the  transver- 
salis and  iliac  fasciae.  On  the  deep  surface  of  the  fascia 


THE  ABDOMEN  241 

lies  a  layer  of  EXTRAPERITONEAL  TISSUE,  which  fills  in  the 
furrow^  between  the  muscles,  thus  presenting  a  fairly  regular 
abdominal  surface,  and  in  which  the  kidneys,  ureters,  renal, 
colic,  and  spermatic  vessels,  and  iliac  vessels  and  lymphatic 
glands  are  embedded.  (The  anterior  crural  nerve  and  lumbar 
nerves,  on  the  other  hand,  are  under,  or  external  to,  the 
fascia.)  On  the  inner  surface  of  the  extraperitoneal  tissue, 
again,  the  peritoneum  lies. 

ABSCESSES  in  this  region  may  occur  either  in  the  extra- 
peritoneal  tissue  or  under  the  psoas  fascia.  Extraperitoneal 
abscesses  may  arise  from  appendix,  kidney,  a  parametritis, 
etc.  ;  may  be  of  considerable  size  and  widely  spread.  Such 
abscesses  tend  to  point  above  Poupart  or  to  enter  the 
pelvis.  Those  which  occur  under,  or  external  to,  the  trans- 
versalis  fascia  generally  point  at  the  iliac  crest  or  above 
Poupart ;  they  rarely  extend  along  the  inguinal  canal  into 
the  scrotum.  Sometimes,  by  following  the  last  intercostal 
or  ilio-hypogastric  nerves,  they  may  pierce  the  lumbar 
fascia,  or  may  pierce  the  quadratus  lumborum,  and  then, 
coming  through  the  external  oblique,  appear  at  Petit's 
triangle.  Those  which  occur  in  the  psoas  sheath  arise 
generally  from  tubercular  disease  of  the  dorsal  or  upper 
lumbar  vertebrae  (Poxx's  DISEASE).  Where  the  disease  is  in 
the  dorsal  region,  the  tubercular  debris  is  first  extruded  into 
the  posterior  mediastinum  in  which  it  gravitates  downwards, 
until  arrested  by  the  diaphragm,  whence,  passing  under  the 
internal  arcuate  ligament  in  company  with  the  psoas  muscle, 
it  enters  the  abdomen  within  the  psoas  sheath.  This  sheath 
directs  it  down  the  posterior  abdominal  wall,  across  the  blade 
of  the  ilium,  under  Poupart's  ligament,  through  the  special 
iliac  compartment  "already  described,  in  which  position  it  lies 
to  the  outside  of  the  femoral  vessels.  Then  the  abscess 
passes  under  the  vessels,  reaches  the  lesser  trochanter,  and  fre- 
quently turns  up  again  and  overlaps  the  vessels  from  the  inside. 
While  this  is  the  typical  course  of  a  PSOAS  ABSCESS,  the  pus 
may  sometimes  escape  from  the  psoas  sheath,  as  for  example 
by  following  one  of  the  lumbar  arteries  between  the  transverse 
processes  of  the  lumbar  vertebrae,  and  then,  running  outwards 
on  the  posterior  surface  of  the  quadratus  lumborum,  pierce 
the  origin  of  the  transversalis,  and  also  the  internal  oblique, 
and  finally  present  in  the  triangle  of  Petit — the  triangular 

16 


242  SURGICAL  ANATOMY 

interval  whose  base  is  formed  by  the  highest  point  of  the  crest 
of  the  ilium,  while  the  sides  are  formed  by  the  free  border  of 
external  oblique  anteriorly,  and  the  latissimus  dorsi  posteriorly. 
The  floor  is  formed  by  the  internal  oblique.  (Above  the 
triangle  the  latissimus  dorsi  overlaps  the  external  oblique.) 
Sometimes  also  the  pus  may  gravitate  into  the  pelvis  through 
the  communication  with  the  pelvic  fascia.  On  the  other 
hand,  pus  from  acetabular  disease,  or  hip  disease  where  the 
acetabulum  is  eroded  and  perforated,  may  extend  upwards, 
and  so  simulate  a  psoas  abscess. 

The  KIDNEYS  are  about  4  inches  long,  fz\  inches  broad, 
and  i \  inches  thick,  the  right  being  shorter  and  thicker  than  the 
left,  which,  however,  is  the  larger.  On  the  anterior  surface 
of  each  kidney  there  is  a  blunt  projection,  formed  by  the 
pressure  of  adjoining  organs,  which  in  the  right  kidney  forms 
a  transverse  ridge,  and  in  the  left  a  blunt  summit.  The  position 
of  the  kidney  may  be  indicated  on  the  posterior  surface  by  four 
lines,  two  horizontal  from  the  spines  of  the  eleventh  dorsal 
and  third  lumbar,  giving  the  upper  and  lower  limits,  and  two 
vertical,  one  i  inch,  and  the  other  3  inches  from  the  vertebral 
spines,  indicating  the  inner  and  outer  limits.  The  hilum 
corresponds  to  the  level  of  the  first  lumbar  spine,  and  is  2  inches 
from  the  middle  line  on  the  right,  and  if  on  the  left  side. 
In  front  the  lower  limit  of  the  kidneys  does  not  extend  below 
the  level  of  the  umbilicus,  corresponding  generally  to  the 
lowest  limit  of  the  thoracic  framework,  and  the  hilum  is  about 
a  finger-breadth  inside  the  tip  of  the  ninth  costal  cartilage. 
The  right  kidney  lies  £  inch  lower  than  the  left,  its  lower 
border  being  ij  inches  from  the  iliac  crest.  The  kidneys 
normally  move  with  respiration,  and  when  this  movement 
is  excessive,  the  kidney  can  frequently  be  palpated  by  one 
hand  in  front,  and  the  other  pressing  forwards  in  the  loin 
when  the  patient  takes  a  long  breath.  While  the  kidney 
rarely  ascends  above  its  normal  position,  it  is  frequently 
found  below  it.  This  in  some  cases  may  be  due  to  a  con- 
genital defect,  the  kidney  normally  ascending  during  foetal 
life  from  the  pelvis  into  its  normal  position.  In  such  cases 
the  kidney  is  generally  fixed  in  the  abnormal  position,  and 
its  vessels  are  short.  Other  congenital  deformities  are  horse- 
shoe kidney,  absence  of  one  kidney,  or  presence  of  a  super- 
numerary kidney. 


THE  ABDOMEN  243 

A  downward  displacement  of  one  kidney,  and  particularly 
the  rigl^t,  frequently  occurs,  the  condition  being  known  as 
movable  kidney.  Normally,  the  kidney  is  kept  in  position 
by  (i)  the  pressure  of  the  abdominal  wall  exerted  on 
it  through  the  viscera,  in  conjunction  with  the  peculiar 
shape  of  its  anterior  surface  already  referred  to  ;  (2)  its 
vessels  ;  (3)  the  attachments  of  the  renal  fascia,  kept  tense 
by  the  fat  of  the  adipose  capsule.  If  the  adipose  tissue 
be  diminished,  these  attachments  become  slack,  and  so 
undue  mobility  i?  allowed.  In  such  cases  great  latitude 
of  movement  may  be  possible,  the  kidney  frequently  being 
found  in  the  pelvis,  and  gastric  dilatation  and  transient 
jaundice  may  be  produced  by  the  traction  of  the  kidney 
upon  the  duodenum.  Floating  kidney  is  the  term  applied 
to  a  similar  but  rare  condition  where  the  kidney  possesses 
a  mesonephron.  As  a  rule,  even  where  the  kidney  is  very 
movable,  its  covering  is  composed  of  loose  fibrous  tissue 
derived  from  its  capsule,  and  not  peritoneum.  The  condition 
is  most  frequently  met  with  in  women,  being  predisposed  to 
by  pregnancy,  causing  relaxation  of  the  abdominal  parietes. 

The  inner  borders  of  the  kidneys  look  inwards  and  also 
forwards,  and  the  lower  extremities  are  wider  apart,  and  are 
directed  more  forward  than  the  upper  extremities.  The 
kidneys  lie  behind  the  peritoneum,  which  is  only  closely  re- 
lated to  the  outer  border,  the  anterior  surface  being  embedded 
in  the  extraperitoneal  fat,  which  in  this  region  is  very  abun- 
dant, constituting  the  capsula  adiposa  of  the  kidney.  This 
in  turn  is  surrounded  by  a  fibrous  investment,  the  fascia 
renalis,  also  composed  of  extraperitoneal  tissue,  which  ,splits 
into  two  layers  to  enclose  the  kidney,  fatty  envelope,  supra- 
renal capsule,  renal  vessels,  and  commencement  of  the  ureter. 
This  fascia  is  attached  above  and  externally  to  the  diaphragm, 
and  then  splits  to  enclose  the  kidney,  the  anterior  layer  passing 
in  front  of  the  kidney,  its  vessels,  and  the  aorta,  and  becoming 
continuous  with  that  of  the  opposite  side,  while  the  posterior 
layer  passes  behind  the  kidney,  and  is  attached  to  the  front 
of  the  spine  along  the  inner  border  of  the  psoas.  Below 
the  level  of  the  kidney  the  two  layers  continue  separately 
in  the  direction  of  the  iliac  fossa,  and  are  gradually  lost. 
This  renal  fascia  sends  in  numerous  trabeculse,  which,  traversing 
the  adipose  layer,  fuse  with  the  proper  capsule  of  the  kidney. 

16— 2 


244  SURGICAL  ANATOMY 

The  proper  capsule  of  the  kidney  is  tough  and  fibrous,  but 
normally  is  not  very  adherent  to  the  kidney  substance.  It 
plays  an  important  part  in  limiting  effusions  within  the 
kidney  substance,  may  practically  form  the  cyst  wall  in 
advanced  hydronephrosis,  and  is  utilized  in  the  operation  of 
nephrorrhaphy. 

Posteriorly,  the  kidneys  are  in  relation  to  the  diaphragm, 
internal  and  external  arcuate  ligaments,  fascia  of  the  psoas 
and  quadratus  lumborum  and  lumbar  fascia,  the  twelfth 
rib  which  crosses  obliquely  at  the  junction  of  the  upper  and 
middle  one-third,  and  transverse  processes  of  the  two  upper 
lumbar  vertebrae.  Externally,  the  right  kidney  is  in  relation 
to  the  liver,  and  the  left  to  the  spleen.  In  front,  the  right 
kidney  is  related  to  the  under  surface  of  the  liver,  ascending 
and  commencement  of  transverse  colon,  and  second  part  of 
duodenum  ;  the  left  to  the  fundus  of  the  stomach,  descending 
colon,  and  pancreas. 

The  relationship  to  the  twelfth  rib  is  of  importance,  as  the 
reflection  of  the  parietal  pleura,  from  diaphragm  to  chest 
wall  takes  place  about  this  level,  and  sometimes  even  below 
it,  and  maintains  this  level  even  when  the  twelfth  rib  is 
rudimentary.  It  is  therefore  wise,  before  commencing  a 
lumbar  operation  on  the  kidney,  to  count  the  ribs  and 
commence  the  incision  fully  f  inch  below  the  lower  border 
of  the  twelfth  rib. 

The  RENAL  ARTERY  arises  from  the  aorta  at  the  level  of 
the  first  lumbar  vertebra.  The  right  is  larger  than  the  left, 
and  passes  under  the  vena  cava.  The  artery  divides  into 
several  large  branches  before  entering  the  kidney.  The 
small  vessels  within  the  kidney  substance  pursue  a  pretty 
straight  course,  and,  as  they  are  practically  end  arteries, 
infarctions  not  infrequently  occur  in  the  kidney  substance. 

The  RENAL  VEINS  empty  into  the  inferior  vena  cava,  the 
left  being  longer  and  crossing  in  front  of  the  aorta,  while 
the  left  spermatic  vein  opens  into  it  at  right  angles.  The 
renal  veins  lie  in  front  of  the  arteries,  which  in  turn  are  in 
front  of  the  ureters. 

The  NERVES  are  derived  from  the  renal  plexus  (from  the 
solar)  and  accompanying  branches  of  the  artery.  The  seg- 
ments of  the  cord  involved  are  from  the  tenth  dorsal  to 
first  lumbar,  through  the  small  and  lesser  splanchnics,  and 


THE  ABDOMEN  245 

in  renal  affections  pain  (e.g.,  dragging  pain  in  movable 
kidney)  ^is  referred  along  the  sensory  nerves  derived  from 
these  segments. 

The  expanded  PELVIS  OF  THE  KIDNEY,  which  is  situated 
partly  within  the  lips  of  the  hilum  and  partly  beyond,  presents 
several  depressions,  or  calyces,  on  which  the  papillae  open. 
The  renal  pelvis  on  the  right  side  is  related  to  the  duodenum 
in  front,  and  vena  cava  on  its  inner  border  ;  on  the  left  to 
the  body  of  the  pancreas  and  jejunum  in  front,  and  aorta 
some  distance  from  its  inner  border. 

Infection  may  reach  the  kidney  by  the  blood-stream,  pro- 
ducing multiple  small  cortical  abscesses,  or  most  commonly 
by  the  ureter.  In  the  latter  case  the  infection  generally 
extends  up  from  the  bladder,  producing  a  pyelitis,  and  by 
further  extension  suppurative  foci  in  the  kidney  substance 
(so  called  '  surgical  kidney  ').  Once  the  ureter  becomes 
blocked,  a  pyonephrosis  occurs.  An  abscess  in  the  tissue 
surrounding  the  kidney  (perinephric  abscess)  may  arise  by 
extension  from  the  kidney  or  from  suppurative  appendicitis, 
empyema  perforating  the  diaphragm,  etc.  Such  abscesses 
generally  point  about  Petit's  triangle,  but,  owing  to  the 
laxness  of  the  tissues,  may  spread  widely  in  the  extraperi- 
toneal  tissues  before  pointing  externally,  sometimes  descending 
into  the  iliac  fossa  or  opening  into  the  colon  or  rectum.  The 
kidney  is  frequently  affected  by  tubercle  (through  the  blood- 
stream). Calculi,  particularly  uric  acid  or  oxalates,  form 
about  the  renal  pelvis,  and,  if  movable,  may  cause  renal 
colic  when  attempting  to  descend  the  ureter. 

Injuries  to  the  kidneys  generally  result  from  severe  crushes, 
the  kidney  being  lacerated  by  pressure  against  the  last  rib, 
or  transverse  processes  and  bodies  of  the  two  upper  lumbar 
vertebrae.  Where  the  capsule  is  ruptured,  a  large  extravasa- 
tion of  blood  and  urine  may  take  place  into  the  extraperi- 
toneal  tissues.  Ruptures  of  the  kidney  are  more  frequently 
recovered  from  than  similar  injuries  of  the  other  viscera, 
owing  to  their  extraperitoneal  position.  Hcematuria  fre- 
quently follows  injuries  to  the  back,  owing  to  the  kidney 
being  crushed  between  the  ilium  and  lower  ribs  in  acute 
anterior  flexion. 

OPERATIONS — Nephrotomy  (incision  into),  N '  ephrolithotomy 
(incision  for  the  removal  of  stone),  N.ephrectomy  (removal), 


246  SURGICAL  ANATOMY 

Nephrorrhaphy  (suturing  kidney  to  parietes  in  normal  posi- 
tion).—  These  operations  may  be  performed  through  a 
lumbar  incision,  commencing  below  the  angle  between  the 
last  rib  and  the  outer  border  of  the  erector  spinae,  and 
extending  down  and  out  to  about  i  inch  above  the 
anterior  superior  spine.  Where  necessary,  the  incision  may 
be  extended  down  and  inwards  into  the  inguinal  region — 
still  extraperitoneal.  The  incision  involves  pretty  free  section 
of  the  muscles  and  subsequent  weakening,  and  especially 
in  women  the  space  between  the  last  rib  and  iliac  crest  is 
frequently  short,  making  removal  of  large  tumours  difficult. 
Further,  it  is  not  possible  to  inspect  the  condition  of  the 
supposed  sound  kidney  prior  to  removal  of  a  diseased  one, 
and  hence  nephrectomy  is  generally  performed  through  an 
abdominal  incision,  the  peritoneum,  of  course,  being  opened. 
In  either  operation  the  vessels  and  ureters  are  ligatured  and 
the  organ  removed.  The  possibility  of  irregular  branches  of 
artery  or  vein  entering  the  kidney  away  from  the  hilum 
should  be  kept  in  mind.  Occasionally  from  disease  the  kidney 
contracts  adhesions  to  surrounding  organs — duodenum,  colon, 
vena  cava,  aorta,  etc. — and  in  order  to  avoid  injury  to  these 
important  structures  it  is  sometimes  necessary  to  remove  the 
kidney  by  a  subcapsular  operation,  which  is  rendered  easier 
by  the  diminished  size  of  the  renal  vessels  in  such  affections. 

In  the  abdominal  operation  the  incision  is  frequently  made 
in  the  linea  semilunaris,  and  the  peritoneum  incised  along  the 
outer  border  of  the  colon,  which  is  then  drawn  inwards  so  as 
to  expose  the  kidney.  Nephrorrhaphy  (nephropexy)  is  generally 
performed  through  the  lumbar  incision,  the  proper  capsule 
of  the  kidney  being  split  along  the  posterior  border,  reflected 
for  fully  J  inch  along  either  side,  and  the  reflected  capsule 
then  stitched  to  the  transversalis  fascia  and  muscles.  The 
wound  is  allowed  to  granulate  so  as  further  to  fix  the  kidney 
by  fibrous  adhesions. 

The  SUPRARENAL  CAPSULES  are  situated  at  the  upper 
extremities  of  the  kidneys,  and  also  extend  along  the  inner 
border,  the  right  being  pyramidal  and  the  left  crescentic  in 
shape.  The  right  is  moulded  against  the  inferior  vena  cava, 
and  the  left  is  close  to  the  aorta.  In  Addisons  disease  these 
capsules,  which  are  closely  connected  with  the  solar  plexus, 
are  generally  affected.  Addison's  disease  is  characterized 


THE  ABDOMEN  247 

by  a  bronzing  of  the  skin,  and  pigmentation  of  the  skin  is 
also  sden  in  pregnancy,  abdominal  tuberculosis,  some  affections 
of  the  liver,  and  carcinoma  of  the  stomach,  due  probably 
likewise  to  some  disturbance  of  the  plexus. 

The  ureter  commences  in  the  dilated  renal  pelvis,  which  is 
connected  to  the  medullary  portion  by  the  calyces  or  infundi- 
bula.  Lying  at  first  in  the  retroperitoneal  tissue  of  the 
abdomen,  it  descends  to  the  pelvic  brim,  which  it  crosses  at 
the  sacro-iliac  articulation,  to  enter  the  pelvis.  About  i  foot 
long,  and  possessing  a  strong  muscular  wall,  the  ureter  is 
described  in  abdominal  and  pelvic  portions.  The  abdominal 
portion  is  related  in  front  and  to  either  side  to  the  peritoneum, 
colic  and  spermatic  vessels,  and  on  the  right  side  to  the 
termination  of  the  ileum,  and  on  the  left  to  jejunum  and  pelvic 
colon.  On  the  left  side  it  lies  immediately  behind  the  inter- 
sigmoid  fossa,  as  it  crosses  the  common  iliac  artery.  Behind, 
the  ureters  lie  on  the  psoas  sheath  and  genito-crural  nerve, 
while  internally  the  right  ureter  is  close  to  the  inferior  vena 
cava,  and  the  left  to  the  aorta  and  inferior  mesenteric  vessels. 

Septic  injection  frequently  travels  by  the  ureter  from  the 
bladder  to  the  kidney,  while,  on  the  other  hand,  pus  or  blood 
coming  from  the  kidney  passes  down  the  ureter  to  the  bladder, 
where  it  may  be  seen,  on  cystoscopic  examination,  dis- 
charging from  the  mouth  of  the  ureter,  and  the  side  of  the 
affected  kidney  thus  decided  with  certainty.  A  ureter 
catheter  is  sometimes  introduced,  with  the  object  of  obtaining 
a  specimen  of  urine  from  one  kidney. 

Calculi  not  infrequently  pass  down  the  ureter  from  the 
kidney,  generally  causing  severe  renal  colic,  with  sickness, 
vomiting;  and  retraction  of  the  testicle,  and  sometimes  they 
may  become  impacted  in  the  ureter,  causing  hydronephrosis 
if  neglected.  In  cases  of  obstruction  of  the  urethra,  urine 
may  accumulate  in  the  ureters  and  pelves,  causing  distension. 

The  ureter  is  not  often  wounded  in  the  abdominal  segment, 
but  is  in  greater  danger  in  the  pelvic  portion,  where  it  has 
been  wounded  through  the  great  sciatic  foramen  in  deep 
gluteal  wounds,  while  it  also  lies  in  the  female  in  close  relation- 
ship to  the  uterus,  and  is  liable  to  damage  in  removal  of  the 
uterus  in  cases  of  extensive  carcinoma.  Where  the  bladder 
is  also  extensively  involved,  the  ureters  have  sometimes  been 
intentionally  cut,  and  their  ends  implanted  into  either  the 


248  SURGICAL  ANATOMY 

vagina  or  the  rectum.  Rupture  of  the  ureter  has  also  occurred 
from  external  violence. 

The  SOLAR  PLEXUS  supplies  the  stomach,  small  intestine, 
liver,  pancreas,  spleen,  and  kidneys  with  sensation ;  controls 
the  blood-supply,  and  also  the  calibre  of  the  bowel.  The 
plexus  receives  branches  from  the  vagus,  phrenic  (through 
its  hepatic  and  suprarenal  divisions) ,  and  also  the  splanchnic 
nerves,  which  arise  from  the  gangliated  cord  of  the  sym- 
pathetic. Injuries  to  the  viscera,  supplied  by  the  sympathetic, 
produce  faintness,  collapse,  and  vomiting,  the  symptoms  being 
more  severe  in  injuries  of  organs  more  closely  associated 
with  the  plexus.  Thus  injuries  about  the  stomach  generally 
produce  profound  symptoms  ;  those  of  the  small  intestine 
serious  symptoms ;  while  those  of  the  ascending  colon,  wrhich 
is  supplied  by  the  superior  mesenteric  plexus,  are  much  less 
serious,  and  those  of  the  descending  colon  and  sigmoid,  sup- 
plied by  the  inferior  mesenteric  plexus  (and  therefore  only 
indirectly  associated  with  the  solar),  still  less  so. 

The  AORTA  gives  off  numerous  large  branches  to  the  in- 
testines, the  cceliac  axis  arid  superior  mesenteric  being  as 
large  as  the  carotid.  These  vessels  form  arches  before  finally 
supplying  the  bowel,  but  embolism  of  even  a  small  branch 
may  lead  to  gangrene  of  the  bowel.  Aneurism  of  the  abdominal 
aorta  occurs  most  frequently  where  the  cceliac  and  other  large 
vessels  are  given  off.  Several  anastomoses  exist  between 
the  visceral  branches  of  the  aorta  and  those  of  the  posterior 
abdominal  parietes  in  connection  with  organs  which  have 
a  large  uncovered  posterior  surface,  such  as  the  liver,  kidneys, 
part  of  the  duodenum,  pancreas,  ascending  and  descending 
colon.  The  vessels  anastomosing  with  these  arc  the  lower 
intercostal,  lumbar,  ilio-lumbar,  circumflex  iliac,  epigastric, 
and  phrenic,  and  the  blood  supplied  by  this  anastomosis 
has  been  sufficient  to  nourish  the  affected  organs  after  embolism 
of  the  cceliac  axis  and  mesenteric  vessels  (Chiene) . 

The  INFERIOR  VENA  CAVA  commences  on  the  right  side  of 
the  fifth  lumbar  vertebra  at  the  junction  of  the  iliacs.  Lying 
on  the  right  side  of  the  spine  as  it  ascends,  it  is  in  front  of  the 
right  lumbar,  and  right  renal  arteries,  which  pass  behind  it, 
while  the  spermatic  artery  lies  in  front,  in  addition  to  small 
intestine,  third  part  duodenum,  pancreas,  portal  vein,  and 
right  lobe  of  liver.  It  receives  the  lower  lumbar  veins,  right 


THE  PELVIS  249 

spermatic,  suprarenal,  and  lower  phrenic,  and  both  renals 
(the  leftlbf  which  is  the  longer,  and  receives  the  left  spermatic, 
or  ovarian,  suprarenal,  and  lower  phrenic  prior  to  entering 
the  cava).  While  in  the  notch  behind  the  liver  the  cava 
receives  the  hepatic  veins  which  return  the  blood  brought 
to  the  liver  by  the  portal  vein  and  hepatic  artery. 

The  THORACIC  DUCT  has  been  wounded,  and  also  cut 
and  ligatured  without  bad  results.  Its  communications  with 
the  azygos  veins  in  the  posterior  mediastinum  and  lymphatic 
vessels  of  the  right  side  may  serve  to  explain  this.  The 
duct  conveys  carcinoma  at  an  early  period  from  certain 
abdominal  affections,  particularly  those  about  the  stomach, 
and  hence,  in  suspected  malignant  disease  of  the  stomach, 
it  is  always  well  to  inspect  the  left  supraclavicular  glands. 
In  many  such  cases  of  carcinoma  the  emaciation  is  largely 
due  to  blocking  of  the  duct  with  carcinoma. 


THE  PELVIS 

The  PELVIS  is  important  surgically,  not  merely  on  account 
of  its  contained  organs,  but  from  its  mechanical  position. 
The  centre  of  gravity  of  the  adult  body  is  just  above  the 
sacro-lumbar  angle,  and  over  the  midpoint  of  a  line  drawn 
between  the  heads  of  the  femora.  In  the  erect  posture  the 
brim  of  the  true  pelvis  forms  an  angle  of  60  degrees  with 
the  horizon,  while  the  base  of  the  sacrum  is  3-f  inches  above  the 
upper  border  of  the  symphysis,  and  the  tip  of  the  coccyx 
just  above  its  lower  border.  This  obliquity  of  the  pelvis  has 
an  effect  in  modifying  shocks  transmitted  to  it,  which  are 
further  distributed  by  certain  arches. 

Thus,  when  in  the  erect  posture,  the  arch  along  which  force 
is  transmitted  is  composed  of  the  sacrum,  sacro-iliac  joints, 
acetabula,  and  intervening  bone,  while  in  sitting  it  is  com- 
posed of  sacrum,  sacro-iliac  joints,  ischial  tuberosities,  and 
intervening  bone.  In  these  arches  the  sacrum  is  compared 
to  a  keystone,  but,  as  Cleland  has  pointed  out,  the  sacrum 
is  really  suspended  between  the  innominate  bones  by  its 
ligaments,  and  is  not  really  a  keystone.  Morris  describes  a 
counter- arch  for  each  of  these  mentioned,  which,  by  converting 
the  arch  into  a  ring,  '  ties'  it,  and  greatly  strengthens  it. 


250  SURGICAL  ANA1OMY 

Thus  the  counter-arch  in  the  erect  posture  is  composed  of 
the  body  and  horizontal  rami  of  the  pubes,  and,  in  the  sitting 
posture,  of  the  rami  of  pubes  and  ischium,  the  arch  being  com- 
pleted, in  both  cases,  by  the  symphysis,  which  therefore  has 
to  stand  a  veiy  considerable  strain.  Thus  in  rickets  the 
symphysis  is  frequently  pushed  forward,  and  sometimes  the 
anterior  arch  yields  almost  entirely,  while  disease  of  the 
symphysis  is  generally  accompanied  by  pain  on  standing  or 
sitting.  As  the  sacro-iliac  joint  and  symphysis  are  sur- 
rounded by  powerful  ligaments,  the  joints  seldom  give  way, 
but  fracture  generally  takes  place  to  one  side  of  them.  Thus 
the  most  common  FRACTURE  OF  THE  PELVIS  is  through  the 
rami  of  both  pubes  and  ischium,  and  this  is  often  associated 
with  tearing  of  the  sacro-iliac  ligaments  or  fracture  of  the 
bone  on  either  side.  Where  the  pelvis  is  crushed  by  laterally 
applied  force  (indirect  violence),  the  sides  of  the  pelvis  tend 
to  be  driven  together,  and  thus  the  posterior  sacro-iliac  liga- 
ments are  torn,  whereas  when  the  force  is  applied  antero- 
posteriorly  (direct  violence),  the  sides  tend  to  be  driven  apart, 
and  so  the  anterior  ligaments  are  torn.  Fractures  of  the 
pelvis  are  very  apt  to  cause  rupture  of  the  urethra,  rectum, 
or  bladder.  The  three  anatomical  portions  of  the  pelvis  fuse 
about  the  seventeenth  year.  The  symphysis  has  been 
divided  to  give  more  room  in  labour  where  the  pelvis  is  con- 
tracted (Sigaultean  operation),  and  separation  has  occurred 
as  the  result  even  of  muscular  violence.  Sacro-iliac  disease, 
which  is  frequently  tubercular,  but  may  be  rheumatoid,  is 
generally  associated  with  much  pain  both  in  standing  and 
sitting,  the  pain  being  referred  to  the  sacrum  along  the  upper 
sacral  nerves,  the  buttock  along  the  gluteal  -nerve,  and  the 
hip  or  knee-joint  along  the  obturator  nerve,  and  occasionally 
to  the  back  of  the  thigh  and  calf  along  the  lumbo-sacral  cord 
and  connection  with  the  great  sciatic.  (The  lumbo-sacral 
cord  and  the  obturator  nerve  pass  over  the  front  of  the 
articulation.)  In  his  operation  for  ectopia  vesicae,  Trendelen- 
burg  divides  the  sacro-iliac  joints  in  order  to  get  the  gaping 
symphysis  to  come  together.  Congenital  tumours,  dermoids, 
and  teratomata,  are  sometimes  found  occupying  the  sacro- 
coccygeal  region,  the  dermoids  frequently  arising  from  remnants 
of  the  post- anal  gut,  which,  like  the  allantois,  is  an  out- 
growth from  the  neurenteric  canal,  and  normally  entirely 


THE  PELVIS  251 

disappears  before  birth.  The  sacro-coccygeal  region  is  also 
the  common  seat  of  attachment  between  attached  foetuses. 
The  sacro-coccygeal  joint  and  surrounding  parts  are  frequently 
the  seat  of  severe  pain  (coccygodynia) ,  which  may  necessitate 
removal  of  the  coccyx.  The  parts  are  supplied  by  the  posterior 
divisions  of  the  second,  third,  and  fourth  sacral,  and  anterior 
and  posterior  divisions  of  the  fifth  sacral,  and  coccygeal 
nerves.  Dislocation  may  also  occur  at  this  joint,  or  it  may 
be  diseased,  the  coccyx  sometimes  projecting  into  the 
rectum.  In  old  age  the  coccyx  becomes  ossified  to  the 
sacrum. 

The  pelvis  is  divisible  into  two  portions — an  upper,  the 
FALSE  PELVIS,  bounded  by  the  iliac  blades  and  above  the  level  of 
the  ilio-pectineal  line,  and  a  lower,  the  TRUE  PELVIS,  bounded 
behind  by  the  sacrum,  coccyx,  and  pelvic  portions  of  the  pyri- 
form  muscles  ;  laterally  by  the  innominate  bone,  covered  by 
the  obturator  internus  ;  in  front  by  the  pubic  bones  and  sym- 
physis  ;  above  by  the  ilio-pectineal  lines  ;  and  below  by  the 
pelvic  diaphragm,  formed  by  the  pyriformis,  sacro-sciatic 
ligament,  coccygeus,  levator  ani,  and  triangular  ligament. 
Within  the  pelvis,  but  below  the  pelvic  diaphragm,  are  the 
ischio-rectal  fossae. 

The  pelvic  cavity  is  lined  by  the  PELVIC  FASCIA,  which  is 
continuous  with  that  of  the  deep  surface  of  the  abdominal 
wall — namely,  the  transversalis  fascia  in  front  and  laterally, 
and  that  of  the  ilio-psoas  and  quadratus  lumborum  behind. 
It  consists  of  parietal  and  visceral  layers,  the  former  running 
down  over  the  brim  of  the  true  pelvis  to  which  it  is  attached, 
and  then  covering  the  obturator  internus  and  pyriforniis,  to 
be  inserted  below  into  the  rami  of  the  pubes  and  ischium  and 
tuber  ischii.  The  portion  of  this  parietal  layer  lining  the  true 
pelvis  is  called  the  obturator  fascia.  In  front  it  forms  the  pos- 
terior layer  of  the  triangular  ligament.  At  the  level  of  the 
origin  of  the  levator  ani  muscles  laterally,  and.  in  a  line  from 
the  back  of  the  symphysis  to  the  ischial  spine  (the  white  line), 
this  parietal  pelvic  fascia  gives  off  a  visceral  layer,  which  runs 
on  the  abdominal  surface  of  the  levator  ani  to  meet  its  neigh- 
bour of  the  other  side,  giving  off  processes  to  the  bladder  and 
rectum  in  both  sexes,  and,  in  addition,  to  the  prostate  and 
vesiculi  seminal es  in  the  male  and  the  vagina  in  the  female. 
This  visceral  layer  is  frequently  called  the  recto-vesical  fascia. 


252 


SURGICAL  ANATOMY 


The  prostate,  neck  of  the  bladder,  vesiculi  seminales  and  base 
of  the  bladder  between  them,  and  last  2j  inches  of  the  rectum 
are  excluded  by  the  attachment  of  the  visceral  layer  of  pelvic 
fascia  from  the  pelvic  cavity.  The  internal  iliac  vessels  and 
branches  lie  on  the  pelvic  aspect  of  the  pelvic  fascia,  and  thus 


FIG.  29. — ANTERIOR  VERTICAL  SECTION  OF  PELVIS  FROM  FRONT. 
(Modified  from  Testut.) 

Recto-vesical  fascia. 

Levator  ani  muscle  between  13  and  14. 

Anal  fascia. 

Obturator  fascia. 

Obturator  membrane. 

Ischio-rectal  fossa. 

Two  layers  of  triangular  ligament  and  compressor 
urethras  and  pudic  vessels  (superficial  layer  of 
triangular  ligament=deep  penneal  fascia). 

Corpus  cavernosum. 

Expansion    from  superficial  layer  of  triangular 

ligament  to  invest  bulb. 
21.  Deep  layer,  superficial  fascia. 

their  perforating  branches  are  ensheathed  by  the  fascia  as 
they  leave  the  pelvis  ;  whereas  the  spinal  nerves  lie  outside  the 
fascia.  The  obturator  vessels  and  nerves  form  an  exception 
to  the  rule,  passing  through  a  special  aperture  in  the  pelvic 
wall.  Separating  the  parietal  pelvic  fascia  from  the  peri- 


I. 

Bladder. 

13- 

2. 

Vas  deferens. 

3- 

Iliac  vessels. 

14. 

4- 

Obturator  vessels. 

J5- 

5- 

Prostate. 

16. 

6. 

Urethra. 

i-j. 

7- 

Prostatic  plexus. 

18. 

8. 

Bulb. 

9- 

Obturator  internus. 

10. 

Obturator  externus. 

19. 

n. 

Iliac  fascia. 

20. 

12. 

White  line. 

THE  PELVIS  253 

toneum  and  uncovered  pelvic  viscera  is  a  loose  layer  of  fatty 
tissue,  corresponding  to  the  extraperitoneal  fatty  tissue  of  the 
abdomen,  with  which  it  is  continuous.  This  tissue  is  also 
continuous  with  the  connective  tissue  of  the  hip  through  the 
obturator  and  sacro-sciatic  foramina,  and  in  it  are  the  iliac 
vessels,  ureters,  lymphatic  glands,  vasa  deferentia,  and  round 
ligaments.  While  this  tissue  is  continuous  throughout,  it  is 
shut  into  compartments  by  sep'ta  running  in  from  the  level 
of  the  sacro-iliac  articulation  between  the  bladder  and  rectum 
in  the  male,  and  uterus  and  rectum  in  the  female.  To  inflam- 
matory conditions  occurring  in  this  layer,  the  term  pelvic 
cellulitis  is  properly  applied. 

The  PELVIC  PERITONEUM,  continuous  with  that  of  the 
abdomen,  partially  lines  the  cavity,  and  possesses  generally 
lax  parietal  but  firm  visceral  attachments.  Owing  to  its 
being  thrown  into  folds  by  underlying  structures,  the  pelvic 
peritoneum  presents  three  fossce — an  anterior,  middle,  and 
posterior — which  are  at  different  levels,  the  anterior  being 
the  highest,  and  the  posterior  the  lowest  (see  Fig.  32). 

The  ANTERIOR  PELVIC  FOSSA  contains  the  bladder,  and  is 
bounded  in  front  by  the  symphysis,  and  behind  by  the  fold  of 
the  ureter — a  peritoneal  ridge  formed  by  the  underlying  PELVIC 
URETER,  which  extends  from  the  postero-lateral  aspect  of 
the  pelvis  at  the  level  of  the  sacro-iliac  articulation  to  the 
lateral  angle  of  the  bladder.  A  paravesical  fossa  may  be  seen 
occupying  either  side  of  this  fossa  when  the  bladder  is  empty. 
The  MIDDLE  PELVIC  FOSSA  is  narrow,  particularly  mesially  ; 
contains  the  vasa  deferentia  and  vesiculi  seminales  in  the 
male,  and  uterus  in  the  female  ;  and  is  bounded  by  the  fold 
of  the  ureter  in  front,  and  by  the  sacro-genital  fold  behind. 
This  sacro-genital  fold  projects  backwards  from  the  posterior 
surface  of  the  bladder  when  empty  as  a  distinct  ridge  fully 
J  inch  deep,  enclosing  the  upper  extremity  of  the  vesiculi  semi- 
nales, the  vasa  deferentia,  and  some  unstriped  muscle  consti- 
tuting the  sacro-genital  ligament,  between  its  layers.  This 
ligament  curves  backwards,  and  is  connected  at  the  back  of 
the  rectum  with  the  lower  end  of  the  anterior  surface  of  the 
sacrum.  This  fold  also  exists  in  the  female,  constituting  the 
utero-sacral,  or  fold  of  Douglas.  The  POSTERIOR  FOSSA  is  the 
lowest,  and  contains  the  rectum,  which,  when  empty,  as  in 
the  case  of  the  bladder,  is  bounded  by  a  lateral  depression  on 


254 


SURGICAL  ANATOMY 


cither  side,  called  the  pararectal  fossa.  This  posterior  fossa 
is  bounded  in  front  by  the  sacro-genital  folds,  and  behind  by 
the  sacrum,  etc.  The  OBTURATOR  FOSSA  presents  on  the 
lateral  pelvic  wall,  being  bounded  by  the  external  iliac  vein 
in  front ;  the  vas  deferens,  or  round  ligament,  below  ;  and  the 


FIG.  30. — POSTERIOR  VERTICAL  SECTION  OF  PELVIS  FROM  BEHIND. 
(Modified  from  Testut.) 


1.  Bladder. 

2.  Vas  deferens. 

3.  Ureter. 

4.  Obturator  vessels. 

5.  Vesiculas  seminales. 

6.  Rectum. 

7.  Anus. 

8.  Sphincter. 

Q.  Obturator  intermix. 


11.  Iliac  fascia. 

12.  White  line. 

13.  Recto-vesical  fascia. 

Levator  ani  muscle  between  13  and  14. 

14.  Anal  fascia. 

15.  Obturator  fascia. 

17.  Ischio-rectal  fossa. 

18.  Pudic  vessels  and  nerve  in  Alcock's  cana1,. 

19.  Posterior  extremity  of  triangular  ligament. 


ureter  behind.  The  pelvic  attachment  of  the  broad  ligament 
in  the  female  divides  this  fossa  into  two  parts,  of  which  the 
posterior  is  termed  the  fossa  ovarii. 

In  addition  to  the  viscera  mentioned,  the  true  pelvis  fre- 
quently contains  coils  of  small  intestine,  pelvic  colon,  and 
portion  of  caecum  and  tip  of  the  appendix,  particularly  when 


THE  PELVIS  255 

the  rectum  and  bladder  are  empty.  The  external  iliac  vessels 
produce  a  peritoneal  fold  at  the  posterior  part  of  the  pelvic 
brim,  and  then,  deviating  outwards  toward  the  under-surface 
of  Poupart's  ligament,  they  form  a  triangle,  bounded  internally 
by  the  ilio-pectineal  line,  and  below  and  in  front  by  Poupart's 
ligament,  which  is  called  the  trigonum  femorale. 

The  AORTA  bifurcates  at  the  level  of  the  fourth  lumbar 
vertebra  on  its  left  side,  forming  the  two  common  iliac  arteries. 


FIG.  31.— VIEW  OF  PELVIC  BASIN  FROM  ABOVE. 
(Modified  from  Testut.) 

1.  Obturator  interims.  5    White  line.  9.  Rectum. 

2.  Levator  ani.  6.   Obturator  vessels.  10.  Coccyx. 

3.  Coccygeus.  7.  Symphysis.  n.  Aperture  for  gluteal  vessels. 

4.  Pyriformis.  S._  Prostate,  etc.  12.  Spine  of  ischium. 

(Dotted  line  indicates  outline  of  lower  border  of  pelvis.) 

These  run  down  and  out  to  the  sacro-iliac  articulations,  where 
they  bifurcate  to  form  the  external  and  internal  iliac  arteries. 
The  external  iliac  artery,  following  the  internal  border  of  the 
psoas  muscle,  first  runs  along  the  pelvic  brim,  and  then, 
tending  outwards,  reaches  the  under-surface  of  Poupart's 
ligament,  and  becomes  the  femoral.  The  internal  iliac  curves 
down  into  the  pelvis,  and  divides  into  anterior  and  posterior 
divisions  at  the  upper  portion  of  the  great  sacrp-sciatic  notch. 


256  SURGICAL  ANATOMY 

The  COMMON  ILIAC  on  both  sides  is  crossed  near  its 
termination  by  the  ureter,  and  is  also  crossed  by  the  sym- 
pathetic fibres  running  from  the  aortic  to  the  hypogastric 
plexus.  Occasionally,  however,  the  ureter  crosses  the  upper 
part  of  the  external  iliac  artery.  The  left  vessel  is  also 
crossed  by  the  inferior  mesenteric  vessels.  The  right  vessel 
is  about  2  inches,  and  the  left  about  if  inches  long.  The 
external  iliac  is  nearly  4  inches  long.  The  course  of  common 
and  external  iliac  vessels  is  indicated  by  a  line  from  a 
point  J  inch  below,  and  to  the  left  of  the  umbilicus,  to  a 
point  on  Poupart's  ligament,  midway  between  the  anterior 
superior  spine  and  the  symphysis  pubis.  The  line  should  have 
a  slight  external  convexity,  and  the  upper  one- third  represents 
the  common  iliac  vessel. 

The  EXTERNAL  ILIAC  artery  is  invested  by  both  peritoneum 
and  extraperitoneal  tissue,  the  latter  (fascia  of  Abernethy) 
sending  in  a  septum  between  the  artery  and  vein.  The  artery 
is  crossed  near  Poupart's  ligament  by  the  geni to-crural  nerve, 
spermatic  vessels,  and  deep  circumflex  iliac  vein.  The 
ovarian  vessels  in  the  female  cross  the  middle  of  the  artery. 
Ligature  of  the  external  iliac  vessel  might  be  required  for 
trauma  or  for  aneurism,  which  at  this  level  generally  affects 
also  the  femoral  artery.  The  ligature  may  be  performed  by 
opening  the  abdomen,  or  by  making  an  incision  parallel  to, 
and  above,  Poupart  through  the  abdominal  wall,  and  then 
shelling  the  peritoneum  upwards.  In  the  abdominal  method 
the  Trendelenburg  position  should  be  used,  and  care  is  neces- 
sary to  avoid  the  vein  (lying  generally  behind  and  to  the  inner 
side),  the  ureter,  and  the  genito-crural  nerve.  In  the  extra- 
peritoneal  method  a  curved  incision  is  made,  4  inches  long, 
commencing  i  inch  above  and  internal  to  the  anterior 
superior  spine,  and  extending  downwards  and  inwards  to  a 
point  ij  inches  above  and  external  to  the  centre  of  Poupart. 
The  superficial  structures,  muscles,  and  transversalis  fascia 
are  divided,  the  peritoneum  exposed  and  reflected,  until  the 
vessel  is  exposed  on  the  inner  border  of  the  psoas. 

The  INTERNAL  ILIAC  is  i|  inches  long.  Its  anterior  division 
gives  off  (a)  in  the  pelvis ;  vesical  and  middle  haemorrhoidal, 
and  in  the  female,  uterine  and  vaginal ;  (b)  extrapelvically ; 
obturator,  internal  pudic,  and  sciatic  branches.  The  posterior 
division  gives  off  ilio-lumbar  and  lateral  sacral  branches  intra- 


THE  PELVIS  257 

pelvically,  and  gluteal  extrapelvically.  The  obliterated  hypo- 
gastric  aster y  constitutes  the  terminal  portion  of  the  internal 
iliac,  which,  in  the  foetus,  runs  up  the  abdominal  wall  to  the 
umbilicus,  to  pass  out  with  the  other  structures  of  the 
cord. 

While  for  some  time  after  birth  the  BLADDER  is  an  abdo- 
minal organ,  and  spindle-shaped,  in  the  adult  it  occupies  the 
pelvis,  although  it  rises  into  the  abdomen  when  distended. 
The  bladder  lies  between  the  symphysis  in  front  and  the 
rectum  or  vagina  behind.  It  rests  in  a  triangular  space, 
formed  by  two  lateral  walls,  composed  of  levator  ani  and 
internal  obturator,  covered  by  pelvic  fascia,  which  converge 
anteriorly  to  the  pubic  symphysis  and  retropubic  fat.  Pos- 
teriorly and  below,  the  third  side  is  formed  by  seminal  vesicles, 
vasa  deferentia,  and  recto-vesical  layer  of  pelvic  fascia,  or, 
in  the  female,  by  anterior  vaginal  wall  and  cervix  uteri. 
Thus,  the  lateral  walls  and  base  of  the  bladder  slope  inwards 
and  downwards  to  the  urethral  or i fie 2,  which  is  the  lowest  and 
also  the  most  fixed  portion  of  the  bladder,  being  held  in  posi- 
tion by  the  pelvic  fascia.  When  the  bladder  is  much  dis- 
tended, the  orifice  is  slightly  depressed,  while,  if  the  rectum  be 
distended,  it  is  slightly  raised.  Normally,  it  lies  behind  and 
slightly  below  the  level  of  the  upper  margin  of  the  symphysis 
pubis.  The  upper  surface  of  the  bladder  and  its  peritoneal 
relations  vary  according  as  it  is  full  or  empty.  The  upper 
surface  of  the  contracted  bladder  is  convex  and  triangular  in 
outline,  the  apex  lying  behind  the  symphysis,  and  giving 
attachment  to  the  urachus,  while  the  postero-lateral  angles 
mark  the  positions  of  the  ureters. 

The  PERITONEUM,  covering  the  urachus  in  front,  forms 
the  anterior  false  ligament,  the  reflection  being  situated  just 
below  the  upper  border  of  the  symphysis  ;  while  laterally, 
being  reflected  about  the  level  of  the  ilio-pectineal  lines, 
it  forms  the  lateral  false  ligaments ;  and  posteriorly,  pro- 
jecting backwards,  as  already  described,  in  a  fold,  it  forms 
the  sacro-genital  fold,  and  then  descends  into  the  pelvis, 
forming  the  recto-vesical  pouch,  which  extends  to  within 
an  inch  of  the  base  of  the  prostate.  When  the  bladder  is 
distended,  the  peritoneum,  in  the  position  of  the  anterior  false 
ligament,  is  raised,  exposing,  perhaps,  a  couple  of  inches 
of  uncovered  bladder  above  the  level  of  the  symphysis 


258  SURGICAL  ANATOMY 

(through  which  the  distended  bladder  may  be  tapped),  and 
the  lateral  line  of  reflection  is  also  raised.     Speaking  generally, 


FIG.  32. — DIAGRAM  OF  MALE  PELVIS.  VIEWED  FROM  ABOVE.  ON  THE 
RIGHT  SIDE  THE  PERITONEUM  HAS  BEEN  FOLDED  OVER,  DISPLAYING 
THE  RIDGES  AND  Foss^,  WHILE  ON  THE  LEFT  THE  PELVIS  is 
SHOWN  CUT  IN  SECTION. 

(Modified  from  Cunningham.) 


1.  Rectum. 

2.  Bladder. 

3.  Sacral  promontory. 

4.  Pararectal  fossa. 

5.  Sacro-  or  genito-rectal  fold. 

6.  Ureter. 

7.  Vesical  artery. 

8.  Plica  transversa  vesicae. 

9.  Urachus. 

10.  Trigonum  femorale. 

11.  Paravesical  fossa. 

12.  Obturator  fossa. 

13.  Obliterated  hypogastric  artery. 


14.  Vas  deferens. 

15.  Deep  epigastric  vessels. 

16.  External  iliac  artery. 

17.  External  iliac  vein. 

1 8.  Internal  iliac  artery  and  obturator  nerve. 

19.  Sacral  nerves. 

20.  End  of  pelvic  mesocolon. 

21.  Sacrum. 

22.  Sacro-iliac  synchondrosis. 

23.  Ilium. 

24.  Iliacus  muscle. 

25.  Rectus  muscle,  with  pyramidalis  muscle  in 

front  and  urachus  to  inner  side. 


when  the  apex  of  the  bladder  is  2  inches  above  the  pubic 
crest,  the  peritoneum  will  be  raised  about  f  inch  above  it,  while, 
when  the  apex  is  midway  between  the  umbilicus  and  pubes, 


THE  PELVIS  259 

the  peritoneum  may  be  ij  to  2  inches  above  it.  Normally, 
the  bladder  will  hold  about  a  pint,  but  in  great  distension, 
when  the  organ  reaches  the  level  of  the  umbilicus,  or  even 
higher,  it  may  contain  2  or  3  quarts.  The  sacro-genital  fold 
then  disappears,  the  surplus  peritoneum  being  taken  up  by  the 
increasing  size  of  the  bladder  ;  but  the  level  of  the  recto- 
vesical  pouch  does  not  appreciably  alter,  save,  perhaps,  where 
the  rectum  is  distended.  An  equilateral  triangle  is  formed  by 
the  prostate  as  an  apex,  the  vesiculi  seminales  as  two  sides, 
and  the  recto-vesical  fold  as  base,  whose  sides  are  about 
ij  inches  long  (EXTERNAL  TRIGONE).  The  bladder  and  rectum 
are  adherent  over  this  area,  through  which,  therefore,  the 
bladder  may  be  tapped  per  rectum.  The  upper  surface  of  the 
bladder  is  related  in  the  male  to  the  pelvic  colon  and  small 
intestine,  and  in  the  female  to  the  uterus  ;  the  lateral  aspect 
is  related  to  the  levator  ani,  and  the  internal  obturator  muscles, 
parietal  pelvic  fascia,  and  vesico-prostatic  venous  plexus. 
Below  and  in  front,  the  pubic  bones,  symphysis,  retropubic 
fat,  vesical  layer  of  pelvic  fascia,  and  anterior  vesical  veins 
are  in  relation  ;  while  the  base  is  related  to  the  rectum,  with 
seminal  vesicles,  vasa  deferentia,  and  recto-vesical  fascia  inter- 
vening in  the  male,  and  to  the  shallow  utero-vesical  pouch, 
cervix,  and  vagina  in  the  female. 

The  RETROPUBIC  FAT  and  cellular  tissue  is  of  importance 
surgically,  as  if,  in  doing  a  suprapubic  cystotomy,  this  tissue 
be  burrowed  into,  a  pocket  is  easily  formed  in  which  material 
may  collect  and  sepsis  be  set  up,  which,  if  it  spreads,  may 
lead  to  the  death  of  the  patient. 

The  muscular  coat  of  the  bladder  is  composed  of  a  reticu- 
lated network  of  bundles,  which  become  more  marked  in 
cases  of  hypertrophy,  producing  fasciculation.  In  cases  of 
distension  the  intervening  mucous  membrane  may  yield, 
producing  a  sacculated  bladder.  In  cases  of  hypertrophy  the 
change  is  most  marked  in  the  anterior  wall.  The  bladder 
is  lined  internally  with  mucous  membrane,  which,  particularly 
when  the  organ  is  empty,  is  thrown  into  folds  by  the  underlying 
muscular  bundles  to  which  it  is  but  loosely  attached  by  lax 
submucous  tissue. 

The  INTERNAL  TRIGONE  forms  an  equilateral  triangle  at 
the  base  of  the  bladder,  whose  sides  are  about  ij  inches 
long,  and  here  the  mucous  membrane  is  smooth,  firmly 

17—2 


260  SURGICAL  ANATOMY 

attached  to  the  underlying  muscle,  and  slightly  raised  above 
that  bounding  its  sides.  At  the  apex  of  the  trigone  is 
the  urethral  orifice,  surrounded  by  a  slightly  raised  ring 
of  mucous  membrane  (annulus  urethralis),  while  at  each 
of  the  basal  angles  of  the  triangle  a  ureter  opens,  having 
traversed  the  bladder  wall  obliquely  for  f  inch.  The  internal 
and  external  trigones  practically  coincide.  A  fine  linear  fold, 
called  the  uvula  vesica,  runs  from  the  urethral  orifice  back- 
wards towards  the  centre  of  the  base  of  the  triangle,  while  it 
is  also  continued  forward  through  the  urethral  orifice  to  the 
floor  of  the  prostatic  urethra,  forming  the  verumontanum. 
This  is  most  marked  in  cases  of  enlarged  prostate,  being 
situated  over  the  middle  lobe.  The  depression  bounding 
either  lateral  wall  of  the  triangle  is  called  a  paratrigonal  fossa, 
while  that  bounding  the  base  is  called  the  retro-ureteric  fossa. 
This  latter  often  becomes  large  in  enlarged  prostate,  contains 
a  quantity  of  ammoniacal  urine  which  the  patient  cannot 
pass  (residual  urine) ,  and  sometimes  a  calculus,  and  is  called  a 
posterior  prostatic  pouch. 

The  arteries  supplying  the  bladder  are  the  superior  and 
inferior  vesical  of  the  interior  iliac,  the  latter  of  which 
is  the  larger,  and  supplies  the  more  vascular  floor.  The 
veins  have  a  plexiform  arrangement  in  the  various  coats, 
and  join  the  internal  iliac.  Those  in  the  region  of  the 
trigone  frequently  become  congested,  and  even  varicose  in  old 
persons,  especially  in  cases  of  enlarged  prostate.  The  lym- 
phatics run  to  the  glands  surrounding  the  iliac  vessels.  The 
motor  nerves  are  derived  from  the  eleventh  and  twelfth  dorsal 
and  first  lumbar,  which  pass  through  the  hypogastric,  pelvic, 
and  vesical  plexuses,  and  the  sensory  nerves  from  the  third 
and  fourth  sacral,  which  pass  direct  to  the  vesical  plexus. 
The  reflex  micturition  centre  is  situated  in  the  lumbar  enlarge- 
ment, and  is  normally  under  control  of  the  brain.  In  same 
spinal  conditions  this  control  is  lost,  and  the  centre  acts 
automatically,  emptying  the  bladder  when  necessary  at 
regular  intervals.  When,  on  the  other  hand,  the  centre  is 
destroyed,  absolute  incontinence  results.  The  trigone  is 
richly  supplied  by  the  vesical  plexus,  which  also  supplies  the 
seminal  vesicle,  vas  deferens,  and  distal  extremity  of  the 
ureter.  As  the  skin  of  scrotum,  and  penis,  and  mucous 
membrane  of  urethra  are  also  supplied  by  these  segments, 


THE  PELVIS  261 

bladder  affections  frequently  cause  pain  referred  to  base  of 
glans  penis,  etc. 

The  female  bladder  has  a  smaller  capacity  than  that  of  the 
male.  There  being  no  prostate,  the  neck  lies  nearer  the 
symphysis,  and  is  very  distensible,  even  permitting  of  a 
calculus  becoming  impacted  in  it.  Indeed,  stones  of  a  diameter 
of  |  inch  have  been  removed  by  forceps  after  dilatation  of  the ' 
urethra.  Through  the  dilated  urethra,  also,  the  orifices  of 
the  ureters  may  be  seen  and  examined.  The  bladder  wall 
and  vagina  are  intimately  connected,  and  vesico  -  vaginal 
fistula  frequently  occur.  The  utero-vesical  fold  of  peritoneum 
extends  down  only  to  the  junction  of  body  and  cervix  of  the 
uterus ;  beyond  that  point  the  cervix  is  loosely  adherent  to 
the  posterior  layer  of  the  bladder,  and  the  vagina  intimately  so. 

Associated  with  defect  in  the  anterior  abdominal  wall,  the 
anterior  wall  of  the  bladder  may  be  absent,  the  posterior  wall 
and  trigone  presenting  as  a  red  vascular  mass.  This  condition 
is  called  ectopia  vesiccz,  or  extroversion  of  the  bladder. 
Hernia  of  the  bladder  may  occur  through  the  femoral  or  in- 
guinal canals,  and  also  through  the  obturator  and  great 
sacro-sciatic  foramina.  Prolapse  of  the  bladder  backwards 
into  the  vagina  is  called  vaginal  cystocele,  and  into  the  rectum 
rectal  cystocele.  Rupture  of  the  bladder,  caused  by  blows 
or  falls  when  the  bladder  is  distended,  generally  occurs  at  the 
upper  and  posterior  surface,  which,  being  covered  by  peri- 
toneum, causes  invasion  of  the  peritoneal  cavity.  The 
bladder  may,  however,  be  wounded,  frequently  about  the  base, 
and  therefore  extraperitoneally,  by  a  fractured  pelvis,  while 
it  has  also  been  wounded  through  the  sciatic  notch,  thyroid 
foramen,  rectum,  abdomen,  etc.  Fistula  may  connect  the 
bladder  with  the  rectum,  colon,  or  vagina  (a  bi-mucous  fistula), 
or  with  the  suprapubic  region,  or  perineum  (muco-cutaneous 
fistulae).  Where  the  bladder  communicates  with  the  bowel, 
flatus  and  even  fsecal  matter  may  be  passed  per  urethram. 
Stones  in  the  bladder  frequently  rest  upon  the  vascular  and 
sensitive  trigone,  causing  pain  and  haemorrhage,  but  some- 
times they  become  arrested  in  one  of  the  pockets  of  mucous 
membrane.  Tumours,  such  as  papilloma  or  epithelioma,  and 
ulcerative  processes,  such  as  tubercle,  frequently  occur  in  the 
region  of  the  trigone.  Most  of  these  conditions  become 
complicated  sooner  or  later  by  cystitis,  or  inflammation  of  the 


262  SURGICAL  ANATOMY 

bladder  wall.  In  order  to  treat  such  conditions  it  is  frequently 
necessary  to  open  the  bladder.  Cyslolcmy  is  generally 
performed  suprapubically,  a  vertical  incision  being  made 
immediately  above  the  pubes,  after  the  bladder  has  been 
distended,  so  as  to  raise  the  peritoneum.  The  superficial 
tissues  are  cut,  recti  and  pyramidales  separated,  transversalis 
fascia  divided,  prevesical  fat  pushed  aside,  and  the  bladder 
exposed  and  treated.  The  bladder  may  also  be  reached 
through  the  perineum,  vagina,  or  rectum,  but  the  latter 
route  is  seldom  employed,  and  is  dangerous.  Stones  are 
sometimes  extracted  entire  per  urethram  in  the  female,  and 
in  the  male  by  previous  crushing  (lithotrity)  and  washing  out 
through  a  large  catheter  (litholopaxy). 

THE  URETHRA. 

The  FEMALE  URETHRA,  ij  inches  long,  runs  downwards 
and  forwards  in  a  slight  curve,  pierces  the  triangular  ligament, 
between  the  layers  of  which  it  is  surrounded  by  the  com- 
pressor urethrae,  and  ends  at  the  external  orifice  i  inch  below 
and  behind  the  clitoris  and  between  the  labia  minora.  The 
posterior  wall  is  closely  associated  with  the  anterior  vaginal 
wall,  the  peritoneum  only  dipping  in  between  the  postero- 
superior  wall  of  the  bladder  itself  and  the  body  of  the  uterus. 
The  canal  normally  is  about  J  inch  in  diameter,  but  is  very 
distensible,  so  that  calculi  may  be  passed  or  extracted  per 
urethram  in  the  female.  Stones  up  to  f-  inch  diameter  may 
be  so  removed.  A  small  vascular  papillomatous  tumour, 
which  is  painful,  may  occur  about  the  orifice  of  the  urethra, 
and  is  called  a  urethral  caruncle. 

The  URETHRA  IN  THE  MALE  is  fully  8  inches  long,  and  in 
addition  to  the  urine,  transmits  the  spermatic  fluid  from  the 
testicles,  and  the  secretions  from  the  prostate  and  Cowper's 
glands.  Leaving  the  narrow  orifice  of  the  bladder,  it  passes 
through  the  prostate  gland,  and  then,  passing  through  the 
triangular  ligament,  enters  the  perineum,  and  penis.  It  is 
described  as  consisting  of  a  prostatic,  membranous,  and 
spongy  portions  ;  and  in  its  course  it  describes  a  double  curve, 
first  passing  down  beneath,  and  then  up  in  front  of  the  pubic 
arch,  and  then  once  more  turning  down  to  enter  the  penile 
portion.  The  first  curve  with  the  convexity  downwards 


THE  PELVIS  163 

is  fixed,  and  begins  and  ends  at  the  level  of  a  horizontal  Hne, 
drawn  antero-posteriorly  across  the  lower  border  of  the 
symphysis,  the  summit  lying  i  inch  below  the  same  point  on 
the  symphysis.  The  second  curve  commences  at  the  point  of 
attachment  of  the  suspensory  ligament,  traverses  the  penis, 
and  is  movable. 

The  PROSTATIC  PORTION  extending  from  the  floor  of  the 
bladder  to  the  prostate  apex  is  the  widest  portion  of  the 
urethra  (J  inch  in  diameter),  is  about  ij  inches  long, 
and  is  almost  vertical.  Wider  at  its  centre  than  at  either 
extremity,  it  begins  opposite  the  centre  of  the  symphysis 
posteriorly,  and  extends  to  a  point  i  inch  behind  and  below 
the  subpubic  angle.  The  verumontanum,  continuous  with  the 
uvula  vesicce  of  the  bladder,  and  distally  with  the  crista 
urethralis,  which  disappears  at  the  membranous  portion, 
forms  a  ridge  on  its  posterior  border,  and  on  its  summit  presents 
an  opening,  leading  upwards  and  backwards  for  nearly  J  inch, 
called  the  prostatic  utricle  (or  sinus  pocularis),  which  is  the 
homologue  of  the  uterus  and  vagina  of  the  female.  The 
ejaculatory  ducts  open  on  either  side  of  this  utricle,  while  the 
larger  prostatic  ducts  open  into  grooves,  the  prostatic  sinuses, 
on  either  side  of  the  verumontanum. 

The  MEMBRANOUS  PORTION  is  the  shortest,  measuring  about 
f  inch  ;  narrowest,  except  the  meatus  (J  inch  in  diameter)  ; 
and  is  also  the  most  fixed,  lying  between  the  two  layers  of 
the  triangular  ligament,  and  surrounded  by  the  fibres  of  the 
compressor  urethra,  which  may  produce  what  is  called 
spasmodic  stricture.  It  is  separated  from  the  subpubic 
ligament  by  the  dorsal  vessels  and  nerves  of  the  penis,  together 
with  loose  connective  tissue. 

The  SPONGY  PORTION  is  the  longest,  over  6  inches,  and  ex- 
tends from  the  anterior  layer  of  the  triangular  ligament  to  the 
meatus.  Almost  immediately  after  piercing  the  triangular 
ligament,  the  urethra  enters  the  bulb  J  inch  from  its  posterior 
extremity,  and  traverses  its  dorsal  aspect,  receiving  the 
orifices  of  the  ducts  of  Cowper's  glands  on  its  lower  wall. 
The  diameter  of  the  spongy  portion  is  considerable  at  the 
bulb,  and  thereafter  is  fairly  uniform,  save  near  the  meatus. 
It  presents  numerous  small  lacunae  and  ducts  of  mucous 
glands,  which  open  obliquely  in  the  direction  of  the  meatus, 
particularly  on  the  floor  of  the  canal.  The  fossa  navicularis 


264  SURGICAL  ANATOMY 

is  a  dilatation  on  the  dorsal  aspect,  situated  just  beyond  the 
meatus.  A  small  recess,  termed  the  lacuna  magna,  sometimes 
opens  off  it.  The  external  meatus  is  the  narrowest  portion  of 
the  entire  canal,  measuring  not  more  than  £  inch  in  diameter. 
As  the  external  meatus  is  the  narrowest  part  of  the  urethra, 
a  catheter  which  will  pass  that  point  will  pass  into  the  bladder 
if  the  canal  be  normal.  The  canal  generally  is  only  a  potential 
one,  and  presents  as  a  vertical  slit  at  the  meatus,  and  in  the 
region  of  the  fossa  navicularis,  and  as  a  horizontal  slit  at  other 
places. 

In  introducing  a  catheter,  the  penis  is  directed  upwards, 
so  as  to  obliterate  the  double  curve,  and,  once  the  catheter 
has  passed  the  fossa  navicularis,  its  point  is  directed  con- 
stantly toward  the  roof  of  the  canal,  as,  if  it  be  small,  it  might 
otherwise  engage  in  the  ducts  opening  on  the  floor.  The 
point  where  difficulty  is  most  likely  to  be  experienced  is  at 
the  junction  of  the  wide  movable  penile  and  narrow  fixed 
membranous  portion,  and  here,  if  the  point  be  allowed  to 
pass  along  the  floor,  which  is  very  dilatable  at  this  point, 
it  will  probably  not  enter  the  narrow  membranous  canal,  but 
rupture  the  urethra,  making  a  false  passage  in  the  bulbous 
portion  in  front  of  the  triangular  ligament.  To  avoid  this 
mistake,  the  handle  of  the  instrument,  which  hitherto  has 
been  lying  on  the  groin  or  abdomen  of  the  patient,  should  now 
be  steadily  raised,  so  as  to  keep  the  point  on  the  firmer  roof, 
and  usually  it  then  slips  in  without  any  application  of  force. 

Stricture  from  gonorrhoea  generally  affects  the  spongy  portion, 
whereas  stricture  following  trauma  (as  rupture  from  a  fall  stride- 
legs)  generally  affects  the  membranous  portion.  A  primary 
syphilitic  sore,  occurring  just  within  the  urethral  orifice, 
may  cause  stricture  at  that  part.  In  cases  of  stricture,  not 
merely  is  the  canal  narrowed,  but  it  frequently  is  rendered 
tortuous,  rendering  catheterization  very  difficult,  and  greatly 
increasing  the  risk  of  making  false  passages.  When  the 
urethra  is  torn,  whether  by  trauma,  as  in  a  fall  stride-legs, 
by  fractured  pelvis,  false  passage,  or  ulcerative  processes, 
EXTRAVASATION  OF  URINE  is  liable  to  occur.  Where  the 
membranous  portion  is  torn,  the  extravasation  takes  place 
between  the  layers  of  the  triangular  ligament,  by  which  it  is 
confined,  until  set  free  by  sloughing,  generally  of  the  anterior 
layer,  when  it  enters  the  perineum.  Where  the  bulbous 


THE  PELVIS  265 

portion  is  affected,  the  urine  is  extravasatcd  in  the  perineum 
between  the  anterior  layer  of  the  triangular  ligament  and  the 
deep  la^er  of  the  superficial  fascia  (Colles's  fascia). 

COLLES'S  FASCIA  is  attached  posteriorly  to  the  base  of  the 
triangular  ligament,  and  laterally  to  the  rami  of  the  pubes  and 
ischium,  and  thus  the  urine,  as  it  accumulates,  is  forced  to  run 
forwards.  Colles's  fascia  is  continuous  with  the  dartos  of  the 
scrotum,  and  superficial  fascia  of  the  penis,  while,  by  a  funnel- 
chaped  process  running  in  front  of  the  cord,  it  communicates  with 
the  superficial  fascia  of  the  abdomen.  Thus  the  extravasated 
urine  first  distends  the  perineum,  then  the  scrotum  and  penis, 
and  then  finds  its  way  on  to  the  front  of  the  abdomen,  whence 
it  is  prevented  reaching  the  thigh  by  the  attachment  of  the 
fascia  to  Poupart's  ligament.  The  urethral  mucous  membrane 
is  supplied  by  the  pudic  nerve. 

MALE  ORGANS  OF  GENERATION. 

The  PENIS  is  described  as  consisting  of  a  root  and  body. 
The  ROOT  consists  of  the  bulb  of  the  corpus  spongiosum,  which 
lies  in  the  middle  line  in  front  of  the  anterior  layer  of  the 
triangular  ligament,  and  of  the  corpora  cavernosa,  which  are 
attached  at  either  side  to  the  rami  of  the  pubis  and  ischium. 
These  three  structures  meet  under  the  pubic  arch,  where  they 
are  fixed  by  strong  connective-tissue  bands,  and  fuse  to  form 
the  BODY  of  the  penis.  They  are  further  supported  by  a 
fascial  suspensory  ligament  from  the  front  of  the  pubis,  and 
are  so  arranged  that  one  of  the  corpora  cavernosa  occupies 
either  side,  while  in  a  sulcus  on  the  deep  surface  lies  the  corpus 
spongiosum,  with  the  urethra  embedded  in  it.  Toward  the 
p^int  of  the  penis,  however,  the  corpus  spongiosum  ascends, 
and,  spreading  out,  forms  the  glans  penis.  The  corpora  caver- 
nosa are  surrounded  by  a  fibrous  envelope,  the  tunica  albu- 
ginea,  and  are  imperfectly  separated  from  one  another  by  the 
septum  pectiniforme.  They  consist,  like  the  corpus  spongiosum, 
of  cavernous  tissue,  and  each  presents,  close  to  the  septum, 
an  artery  to  the  corpus.  In  gonorrhceal  affections  the  corpus 
spongiosum  may  be  rendered  indistensible,  so  that  in  erection 
of  the  penis  it  remains  contracted,  thus  producing  curvature 
of  the  organ.  Superficially  the  organ  is  enveloped  in  a  thin 
skin,  which,  owing  to  the  lax  subcutaneous  tissue,  is  very 


266  SURGICAL  ANATOMY 

mobile.  Thus  it  is  necessary  in  performing  circumcision  to 
see  that  an  excessive  amount  of  skin  is  not  pulled  forward 
and  removed.  The  subcutaneous  tissue,  traversed  by  the 
dorsal  vein  of  the  penis,  is  very  lax,  and  becomes  much  swollen 
when  cedematous  or  when  extravasation  of  urine  has  occurred. 

Under  the  subcutaneous  tissue  is  the  fascia  penis,  which  is 
continuous  with  the  fascia  of  Colles  in  the  perineum.  The 
prepuce  is  formed  of  a  reduplication  of  the  skin,  which  covers 
the  glans  and  neck  of  the  penis.  It  is  attached  on  the  under 
surface  to  the  glans  by  the  franum.  Where  the  prepuce  is 
long  and  so  narrow  that  it  cannot  be  retracted  from  the  glans, 
the  condition  is  known  as  phimosis.  Where  the  prepuce, 
having  been  drawn  back,  forms  a  constriction  round  the  base 
of  the  glans  and  cannot  be  returned,  the  condition  is  called 
paraphimosis.  The  lax  tissue  about  the  corona  enables  the 
Hunterian  chancre  to  develop  characteristically,  with  marked 
induration  ;  whereas  on  the  glans  the  submucous  tissue  is 
practically  absent,  and  the  mucous  membrane  very  adherent. 

Certain  congenital  defects  may  occur  in  the  penis.  The 
cloaca  is  divided  into  an  anterior  urogenital  canal,  and  a 
posterior  rectum,  by  the  coalescence  of  two  lateral  folds.  The 
upper  portion  of  the  canal  receives  the  ureters  and  forms 
the  bladder,  and  the  lower  portion  forms  the  prostatic  and 
membranous  portions,  receives  the  ducts  of  Wolff  and  Mutter, 
and  opens  in  front  of  the  anus  as  the  urogenital  sinus.  At 
the  apex  of  this  sinus  a  small  genital  tubercle  appears,  and  on 
either  side  a  genital  fold,  while  posteriorly  the  sinus  is 
separated  from  the  rectum  by  the  perineal  septum.  In  the 
male  the  penis  is  formed  from  the  genital  tubercle,  which 
elongates,  while  a  furrow  appears  on  its  ventral  aspect.  This 
furrow  deepens,  the  lateral  margins  curve  round  the  groove 
and  coalesce  at  the  median  raphe,  and  thus  the  spongy  urethra 
is  formed.  This  process  of  fusion  proceeds  from  behind, 
forwards.  By  the  coalescence  of  the  genital  folds,  the  scrotum 
is  formed.  In  the  female  the  tubercle  forms  the  clitoris  and 
the  folds  the  labia  majora,  while  the  ducts  of  Miiller  coalesce 
to  form  the  uterus  and  vagina.  Hypospadias,  where  the 
imperfect  urethra  opens  on  the  ventral  surface  of  the  penis, 
may  be  complete,  the  urethra  opening  at  the  base  of  the 
penis,  or  the  scrotum  may  even  be  cleft  (the  testicles  partially 
descended  or  retained) ,  and  the  urethra  open  behind  it,  the  parts 


THE  PELVIS  267 

thus  resembling  the  female  organs  (pseudo-hermaphroditism). 
In  less  severe  cases  the  urethra  may  open  under  the  glans  or 
body  of  the  penis.  In  epispadias  the  penis  has  either  been  cleft 
from  above  or  has  become  twisted.  Usually  the  organ  is  badly 
developed,  and  the  severer  forms  are  frequently  associated  with 
extroversion  of  the  bladder. 

The  penis  is  supplied  by  branches  of  the  internal  pudic 
artery,  the  blood  returning  directly  or  through  the  dorsal  vein 
to  the  prostatic  plexus.  The  nerves  are  derived  from  the 
internal  pudic  and  hypogastric  plexus,  the  latter  supplying 
the  erectile  tissue.  The  pudic  supplies  the  greater  part  of 
the  skin,  and  also  the  muscles  and  mucous  membrane  of  the 
urethra.  Thus  urethral  irritation  frequently  gives  rise  to 
erection  of  the  penis  (e.g.,  gonorrhceal  chordee),  and  a  similar 
result  may  be  caused  by  the  collection  of  smegma  under  the 
prepuce,  while  it  is  possible  that  such  forms  of  irritation  may 
also  give  rise  to  spasm  of  the  urethral  muscles. 

The  PROSTATE  has  been  compared  in  size  and  shape  to  a 
Spanish  chestnut.  It  is  ij-  inches  long,  ij  inches  broad,  and 
J  inch  in  antero-posterior  depth.  Normally  it  weighs  6  drams, 
but  may  be  considered  to  be  enlarged  when  it  weighs  an  ounce 
and  measures  2  inches  from  side  to  side.  Its  base  is  firmly 
attached  to  the  base  of  the  bladder,  and  its  apex,  directed 
downwards  and  forwards,  is  related  to  the  posterior  layer  of  the 
triangular  ligament  and  the  compressor  urethrae  muscle.  It 
is  situated  about  J  inch  below  the  symphysis  pubis,  and  ij  to 
2  inches  from  the  anus.  It  is  traversed  by  the  urethra,  which 
runs  almost  vertically  through  it,  with  a  slight  anterior  con- 
cavity at  the  junction  of  its  anterior  one- third  with  the  pos- 
terior two-thirds,  and  emerges  just  in  front  of  its  apex.  The 
pre-urethral  segment -is  mainly  composed  of  smooth  muscular 
tissue,  and  is  separated  from  the  pubis  by  fatty  tissue  and  its 
own  capsule.  The  retro  -urethral  segment  presents  two  lateral 
lobes  not  separated  superficially,  and  an  upper  wedge-shaped 
portion  or  so  -  called  middle  lobe,  which  lies  immediately 
beneath,  the  trigone,  and  is  separated  from  the  underlying 
lateral  lobes  by  the  ejaculatory  ducts,  which,  entering  the  pros- 
tate posteriorly,  run  downwards,  forwards,  and  inwards,  to 
enter  the  urethra  close  together  on  the  summit  of  the  veru- 
montanum,  which  occupies  the  posterior  wall  of  the  prostatic 
urethra. 


268  SURGICAL  ANATOMY 

The  lateral  lobes  contain  a  considerable  proportion  of 
glandular  tissue.  The  glands  are  irregularly  arranged,  are 
lined  by  columnar  epithelium,  and  their  ducts  pierce  the  floor 
of  the  urethra  on  either  side  of  the  verumontanum.  The  un- 
striped  muscular  tissue  is  best  developed  in  the  cortical  portion 
of  the  gland,  and  in  that  surrounding  the  urethra.  Surround- 
ing .the  prostate,  and  particularly  occupying  a  deep  sulcus 
between  the  base  of  the  bladder  and  the  mass  of  the  gland, 
is  a  rich  venous  plexus,  the  vesico-prostatic  plexus.  These 
veins  are  tortuous  and  well  supplied  with  valves,  but  in  cases 
of  prostatic  enlargement  they  frequently  become  dilated  and 
varicosed,  and,  indeed,  they  frequently  play  a  considerable 
part  in  rapidly  occurring  urethral  obstruction  caused  by  pro- 
static  enlargement.  In  addition  to  its  own  proper  capsule, 
composed  of  connective  tissue  and  unstriped  muscular  fibres, 
the  prostate  possesses  a  tough  fibrous  capsule,  derived  from  the 
recto-vesical  layer  of  pelvic  fascia,  which  encloses  both  the 
gland  and  the  venous  plexus. 

Prostatitis,  or  inflammation  of  the  prostate,  is  generally, 
when  acute,  due  to  urethral  infection,  frequehtly  gonor- 
rhoea, and  may  give  rise  to  prostatic  abscess,  which  may 
be  single  or  multiple.  Such  abscesses,  if  untreated,  gener- 
ally burst  into  the  urethra,  sometimes  into  the  rectum, 
and  occasionally  into  both,  causing  a  fistula.  They  may 
also  discharge  into  the  pelvic  cellular  tissue  and  point  above 
Poupart,  or  even  in  the  perineum,  but  this  is  unlikely,  as 
the  pubo-prostatic  ligaments  of  the  pelvic  fascia  are  dense, 
and  cut  off  the  prostate  from  the  pelvis  on  the  one  hand, 
while  the  prostatic  capsule  is  continuous  with  the  lower  border 
of  the  posterior  layer  of  the  triangular  ligament  on  the  other. 
Prostatic  abscess  is  acutely  painful,  owing  to  this  dense  en- 
capsulation ;  and  as  the  gland  derives  its  nerve-supply  from  the 
lower  three  dorsal  (especially  the  tenth)  and  upper  three  sacral 
segments,  the  pain  may  be  referred  over  a  wide  area,  between 
the  tip  of  the  last  rib  and  soles  of  the  feet.  The  lymphatics 
pass  to  glands  situated  on  the  pelvic  wall  between  the  external 
and  internal  iliac  vessels.  A  thrombo-phlebitis  may  be  caused 
by  invasion  of  the  prostatic  plexus.  Prostatic  abscesses  may 
be  evacuated  by  a  mesial  perineal  incision  between  the  bulb 
and  the  anus  through  the  skin,  cellular  tissue,  perineal  body 
(a  mass  of  fibrous  and  fatty  tissue),  base  of  the  triangular  liga- 


THE  PELVIS  269 

ment,  compressor  urethrae,  levator  ani,  prostatic  capsule, 
and  gla^id  substance.  Chronic  inflammatory  conditions  of 
the  prostate  are  generally  due  to  tubercle,  affecting  the  vesiculi 
seminales,  testicles,  or  bladder. 

SENILE  PROSTATIC  HYPERTROPHY,  occurring  after  the  age  of 
fifty- three,  is  the  most  common  affection  of  the  gland,  generally 
due  to  irregular  new  gland-like  formation.  The  prostatic 
urethra  is  elongated,  compressed  laterally,  and  its  curvature 
increased,  the  outlet  of  the  bladder  being  raised,  and  hence 
micturition  is  impeded,  and  the  posterior  prostatic  pouch  is 
liable  to  form.  Frequently  also  the  urethra  may  become 
twisted,  owing  to  unilateral  enlargement.  Owing  to  the  altera- 
tion in  length  and  curve  of  the  prostatic  urethra,  it  is  frequently 
necessary  to  use  a  prostatic  catheter  in  enlarged  prostate.  A 
gum-elastic  coude  catheter  may  also  be  employed  with  advan- 
tage. In  such  cases  the  gland  may  be  removed  by  a  suprapubic 
operation,  or  through  the  perineum  (prostatectomy),  or  it  may 
generally  be  caused  to  atrophy  by  division  of  the  vasa  defer- 
entia,  or  by  castration.  In  the  former,  while  the  prostatic 
urethra  is  of  course  much  damaged  in  removal  of  the  gland, 
the  external  capsule  remaining  intact  prevents  the  risk  of 
extravasation  of  urine,  while  in  the  latter  the  perineal 
wound  affords  free  drainage.  The  function  of  the  prostate 
is  supposed  to  be  the  secretion  of  a  thin  milky  acid  fluid, 
which  acts  as  a  vehicle  for  the  spermatozoa,  and  stimulates 
them  to  activity.  While  it  affords  support  to  the  urethra, 
it  probably  does  not  assist  micturition. 

The  vesiculi  seminales,  about  2  inches  long,  roughly  tri- 
angular in  section,  and  presenting  a  tuberculated  appearance, 
are  situated  at  the  base  of  the  bladder,  to  which  their  anterior 
surfaces  are  applied,  while  their  posterior  surfaces  are  moulded 
on  the  anterior  rectal  wall.  The  upper  extremities  are  wide 
apart,  are  partially  invested  by  the  peritoneum  of  the  recto- 
vesical  pouch,  and  are  separated  from  contact  with  the  bladder- 
wall  by  the  termination  of  the  ureters,  while  the  pointed 
lower  extremities  lie  close  together  in  the  transverse  fissure 
at  the  base  of  the  prostate,  where  they  join  the  outer  aspect 
of  the  corresponding  vas,  from  which  point  the  common 
ejaculatory  ducts  pass  down  close  together  through  the  pros- 
tate, to  open  on  the  summit  of  the  verumontanum.  The 
vesiculi  seminales  are  enclosed  in  a  sheath  derived  from  the 


270 


SURGICAL  ANATOMY 


rectovesical  fascia.  They  may  be  affected  by  acute  or  chronic 
inflammatory  processes.  The  former,  frequently  gonorrhoea!, 
may  lead  to  abscesses,  which  may  burst  into  the  peritoneum, 
rectum,  or  perineum.  The  latter  are  generally  secondary  to 
tubercular  epididymitis.  The  vesiculi  seminales  may  be 
reached  by  a  curved  incision  in  front  of  the  anus. 

The  vas  deferens,  some  18  inches  long,  and  extending  a 
distance  of  about  12  inches,  continues  the  canal  of  the  epi- 


1(5 


FIG.  33.— THE  VISCERA  OF  THE  MALE  PELVIS  (LATERAL  VIEW). 
(From  Buchanan's  "Anatomy.") 


1.  Pelvic  colon. 

2.  Line  of  peritoneal  reflection. 

3.  Ureter. 

4.  Vas  deferens. 

5.  Vesicula  seminalis. 

6.  Bladder. 

7.  Urachus. 

8.  Symphysis  pubis. 

9.  Triangular  ligament  of  urethra. 
10.  Corpus  cavernosum. 


11.  Corpus  spongiosum. 

12.  Bulb  and  bulbo-cavernosus. 

13.  Colics'  fascia. 

14.  Perineal  pouch. 

15.  Membranous  urethra. 

1 6.  Cowper's  gland. 

17.  Prostate  gland  and  capsule. 

1 8.  Anus. 

19.  Levator  ani  (cut). 


didymis  to  the  ejaculatory  duct.  It  may  be  divided  into  an 
abdominal  and  external  portion.  From  the  point  where  it 
opens  into  the  ejaculatory  ducts,  the  vas  runs  upwards  along 
the  inner  border  of  the  vesiculi  seminales,  and  becomes  wider 
and  tortuous  and  sacculated  for  a  short  distance,  this  portion 
being  called  the  ampulla.  At  the  apex  of  the  vesiculi  it  passes 
between  the  ureter  and  bladder,  and  then  turns  forwards,  up- 
wards, and  outwards  along  the  lateral  pelvic  wall,  immedi- 


THE  PELVIS  271 

ately  under  the  peritoneum,  and  crosses  the  vesical  vessels, 
obturator  vessels,  and  nerve,  and  obliterated  hypogastric 
artery.  On  reaching  the  pelvic  brim,  it  crosses  the  ileo- 
pectineal  line  fully  ij  inches  from  the  pubic  spine,  and  then 
runs  forwards  and  outwards,  turns  round  the  outer  side  of  the 
deep  epigastric  artery,  and  enters  the  inguinal  canal  by  the 
internal  ring.  In  the  inguinal  canal  it  is  joined  by  the  other 
structures  of  the  spermatic  cord,  to  which  it  lies  posterior, 
and  runs  downwards,  inwards,  and  a  little  forwards  to  the 
external  ring,  after  emerging  from  which  it  turns  downwards 
over  the  pubic  crest.  Then,  leaving  the  other  structures  of 
the  cord,  and  becoming  thinner  and  tortuous,  it  passes  down 
along  the  inner  side  of  the  epididymis,  with  which  it  becomes 
continuous  at  the  globus  minor. 

The  spermatic  cord  consists  of  the  vas  deferens  and  cre- 
master  muscle,  artery  to  the  vas,  cremasteric  and  spermatic 
arteries,  pampiniform  plexus  of  veins,  genito-crural  and  sym- 
pathetic nerves,  and  lymphatics.  The  vas  deferens  lies  at  the 
posterior  aspect  of  the  cord,  and  imparts  a  firm,  cord-like 
sensation  to  the  examining  fingers.  It  has  been  ruptured  in 
severe  exertion,  and  is  sometimes  tied  in  cases  of  enlarged 
prostate. 

The  TESTICLE. — The  epididymis,  composed  of  a  much- 
convoluted  tube  some  20  feet  long,  is  applied  to  the  posterior 
border  of  the  testicle,  from  which  it  is  separated  by  an  involu- 
tion of  the  serous  covering,  forming  a  groove  called  the  digital 
fossa.  It  presents  a  body  connecting  globular  upper  and  lower 
extremities,  the  former  and  larger  being  called  the  globus 
major,  and  the  latter  the  globus  minor.  The  tube  begins  in 
the  globus  major,  where  it  receives  the  seminal  fluid  through 
some  twenty  minute  vasa  efferentia,  which  pierce  the  tunica 
albuginea  to  reach  it,  and  ends  at  the  globus  minor  in  the 
vas  deferens.  Attached  to  the  globus  major,  one  or  more 
small  pedunculated  bodies,  called  hydatids  of  Morgagni,  are 
frequently  present,  and  above  the  globus  major  a  similar,  but 
larger,  body,  called  the  organ  of  Giraldes,  or  paradidymis,  is 
occasionally  met  with.  These  bodies  probably  give  rise  to 
certain  forms  of  hydrocele  and  spermatocele.  The  epididymis 
is  covered  by  the  tunica  vaginalis  on  its  exposed  parts, 
except  over  the  greater  portion  of  its  posterior  border.  It 
is  chiefly  by  this  exposed  border  of  epididymis  that  the 


272  SURGICAL  ANATOMY 

testicle    is    fixed   in   situ,    where   it   remains    even    in   large 
hydroceles. 

The  testicle  body,  about  ij  inches  long,  i  inch  from  before 
backwards  and  rather  less  in  thickness,  is  suspended  in  the 
scrotum,  with  its  long  axis  directed  upwards,  slightly  forwards, 
and  outwards.  The  left  testicle  hangs  at  a  lower  level  than 
the  right,  and  this  is  given  as  one  reason  for  the  prevalence 
of  varicocele  on  the  left  side.  The  testicle  is  enveloped  in  a 
tough  white  inelastic  coat  called  the  tunica  albuginea,  which 
sends  in  septa  to  its  interior,  and  which  is  perforated  by  the 
vessels  and  lymphatics  at  the  posterior  border,  where  the 
tunic  and  septa  meet,  forming  a  fibrous  mass  called  the 
mediastinum  testis  (corpus  Highmori).  It  is  partly  owing  to 
the  unyielding  character  of  this  coat  that  acute  affections  of 
the  testicle  are  generally  very  painful. 

The  TUNICA  VAGINALIS  resembles  the  peritoneum,  from 
which  it  is  derived,  in  structure  and  also  in  its  relationship  to 
the  testicle  which  it  encloses.  It  is  a  shut  sac  into  which  the 
testicle  is  invaginated.  Hence  there  is  a  visceral  layer  envelop- 
ing the  testicle,  dipping  into  the  digital  fossa,  and  covering  the 
epididymis,  save  at  the  point  of  exit  of  the  various  structures 
of  the  cord,  and  a  parietal  layer  which  lines  the  scrotal  sac. 
In  HYDROCELE  of  the  tunica  vaginalis  the  sac  may  attain  a  very 
large  size,  holding  many  pints,  and  when  tapping  such  condi- 
tions in  order  to  draw  off  the  fluid,  it  is  important  to  remember 
that  the  testicle  lies  on  the  posterior  surface,  a  short  distance 
from  the  bottom.  Distension  of  the  tunica  vaginalis  with 
blood  is  called  hcematocele. 

The  testicle  is  supplied  with  blood  by  the  spermatic 
artery,  a  branch  of  the  aorta,  which  traverses  the  cord 
to  reach  it,  and  anastomoses  with  the  artery  to  the  vas. 
The  blood  is  returned  by  a  series  of  veins  which,  issuing 
on  the  posterior  border  of  the  testis,  form  a  dense  plexus 
called  the  pampiniform  plexus.  This  plexus  is  of  impor- 
tance surgically,  as  it  frequently  becomes  varicosed,  particu- 
larly on  the  left  side,  giving  rise  to  the  condition  known 
as  VARICOCELE.  In  addition  to  the  fact  that  the  left  testicle 
hangs  lower  than  the  right,  there  are  several  anatomical 
reasons  for  the  predominance  of  left-sided  varicocele  :  On  the 
right  side  the  spermatic  vein  (which  receives  the  blood  from 
the  plexus)  is  valved,  and  discharges  its  blood  obliquely  into 


THE  PELVIS  273 

the  inferior  vena  cava,  whereas  on  the  left  it  is  frequently  not 
valved,  and  discharges  its  blood  at  right  angles  into  the  renal 
vein.  Further,  the  left  vein  is  subject  to  pressure  from  a 
distended  colon  or  sigmoid.  Some  small  veins  also  run  up 
along  the  vas  accompanying  its  artery.  The  lymphatic  vessels 
of  the  testicle  pass  up  along  the  cord  to  the  lumbar  lymphatic 
glands.  The  nerve-supply  is  derived  from  the  tenth  dorsal 
segment  through  the  aortic  and  renal  plexuses,  and  com- 
municates on  the  lower  part  of  the  vas  with  branches  from  the 
hypogastric  plexus.  Thus,  kidney  and  testicle  are  closely 
associated  in  nerve-supply,  and  the  testicle  is  in  direct  com- 
munication with  the  solar  plexus  and  semilunar  gangliae, 
which  are  associated  with  the  termination  of  the  vagus. 
Hence,  injury  to  the  testicle  frequently  causes  collapse  and  a 
marked  tendency  to  vomit,  while  pain  is  generally  felt  in  the 
renal  region  in  testicular  neuralgia,  and  conversely  the  testicle 
is  retracted  in  passage  of  renal  calculus,  etc.  The  epididymis 
receives  its  nerve-supply  from  the  pelvic  plexus.  The  artery 
to  the  vas — a  branch  of  one  of  the  vesical  arteries — accompanies 
it  to  the  testicle,  where  it  anastomoses  with  branches  of  the 
spermatic  artery.  The  vesiculi  seminales  are  supplied  by  the 
interior  vesical  artery.  Both  vasa  and  vesiculi  are  supplied  by 
branches  of  nerve  from  the  hypogastric  plexus. 

Many  of  the  affections  to  which  the  testicle  is  liable  resemble 
in  outward  appearance  an  inguinal  scrotal  hernia.  Hydrocele 
of  the  tunica  vaginalis,  and  of  the  cord,  and  varicocele  have 
already  been  described. 

The  testicle  itself  may  be  affected  by  (a)  tubercle,  which 
first  affects  the  epididymis  (epididymitis) ,  and  is  chronic  ; 
(b)  gonorrhoea,  which  also  first  affects  the  epididymis,  but  is 
acute  (epididymitis)  ;  (c)  syphilis,  which  first  affects  the  body 
of  the  testicle  (orchitis)  ;  and  (d)  sarcoma,  which  rapidly  in- 
volves both  body  and  epididymis,  and  spreads  up  the  cord. 
Sarcoma  is  very  malignant,  and  might  almost  be  described  as 
subacute,  the  lungs  rapidly  becoming  involved,  unless  early 
castration  be  performed.  The  testicle  may  retain  its  fcetal 
position  within  the  abdomen  (cryptorchismus) ,  or  it  may 
descend  to  about  the  position  of  the  external  abdominal  ring, 
and  resemble  an  inguinal  bubonocele,  or  hernia,  which  has  not 
descended  into  the  scrotum.  To  this  form  of  testicular  dis- 
placement, as  well  as  that  first  described,  the  term  undescended 

18 


274  SURGICAL  ANATOMY 

testicle  may  be  applied.  Sometimes  also  the  testicle  may 
descend,  but  becomes  turned — inversion  of  the  testicle — so  that 
it  lies  in  front  of  the  tunica  vaginalis,  and  would  therefore  be 
liable  to  be  wounded  in  the  ordinary  method  of  tapping  a 
hydrocele.  Where  the  testicle  has  not  fully  descended, 
attempts  may  be  made  to  bring  it  down  by  operation  and  fix 
it  in  position,  and  if  these  attempts  do  not  succeed,  it  is 
generally  safer  to  remove  it,  lest  malignant  degeneration  occur. 

In  removing  the  testicle — castration — it  is  generally  ad- 
visable to  cut  the  vas  far  up,  so  as  to  get  beyond  the  disease, 
if  possible  ;  to  fix  the  cut  end  to  the  abdominal  parietes  after 
ligature  and  disinfection  ;  and  to  ligature  the  other  structures 
of  the  cord  separately. 

The  scrotum,  in  which  the  testicles  are  lodged,  consists 
originally  of  two  lateral  folds,  one  on  either  side  of  the  uro- 
genital  furrow.  In  the  female  these  folds  remain  separate, 
and  form  the  labia  majora.  In  the  male  they  coalesce,  the 
median  raphe  marking  the  line  of  coalescence.  The  integument 
of  the  scrotum  is  thin  and  delicate,  and  the  subcutaneous 
tissue  is  devoid  of  fat,  and  contains  a  layer  of  unstriped 
muscle,  called  the  dartos  tunic,  by  the  contraction  of  which  the 
scrotum  may  be  thrown  into  folds.  These  folds,  or  rugae, 
frequently  lodge  dirt,  which,  causing 'irritation,  may  set  up 
eczema.  Chimney-sweep's  cancer,  which  occurs  on  the  scrotum, 
was  supposed  to  be  due  to  soot  lodging  in  these  crevices.  On 
the  other  hand,  the  skin  is  very  distensible,  as  is  seen  in  large 
hydroceles,  herniae,  etc.,  and  when  thus  stretched  is  fairly 
translucent,  enabling  the  translucency  of  a  contained  swelling 
to  be  tested  by  transmitted  light.  The  subcutaneous  tissue  is 
lax,  and  is  readily  affected  in  oedematous  swelling  and  ele- 
phantiasis. The  interior  of  the  scrotum  is  divided  into  two 
by  an  incomplete  septum,  derived  partly  from  the  dartos  tunic. 
The  left  compartment  hangs  lower  than  the  right,  and  each 
is  lined  by  separate  tunica  vaginalis,  infundibuliform,  cre- 
masteric,  and  intercolumnar  fasciae.  The  scrotum  is  supplied 
with  blood  by  superficial  perineal  branches  of  the  internal 
pudic  posteriorly,  and  external  pudic  branches  of  the  femoral 
anteriorly.  The  nerves  are  derived  from  superficial  perineal 
branches  of  the  internal  pudic,  perineal  branches  of  small 
sciatic,  and  from  the  ilio-inguinal  nerve.  The  lymphatics  run 
to  the  inguinal  glands. 


THE  PELVIS  275 

FEMALE  ORGANS  OF  GENERATION. 

The  UTERUS  is  3  inches  long,  2  inches  wide  at  its  broadest 
part,  a«id  its  canal,  including  the  cervical  portion,  is  2\  inches 
long.  It  weighs  about  i  ounce.  It  is  composed  of  an  upper 
expanded  portion,  the  fundus,  which  ends  at  the  level  of  the 
Fallopian  tubes,  a  body,  and  a  cervix,  the  junction  of  the  two 
latter  being  occasionally  marked  externally  by  an  isthmus, 
while  internally  there  is  a  marked  constriction  at  this  point 
called  the  internal  os.  The  cervix  is  about  i  inch  long,  and 
is  invaginated  into  the  vagina,  so  that  its  lower  extremity, 
or  external  os,  projects  into  the  lumen  of  the  vagina,  and  rests 
against  its  posterior  wall.  Thus  the  cervix  is  divided  into 
supravaginal  and  vaginal  segments.  As  the  uterus  is  normally 
both  anteflexed  (angle  of  120  degrees)  and  anteverted,  it  meets 
the  vagina  at  a  considerable  angle,  and  the  anterior  vaginal 
wall  therefore  is  shorter  than  the  posterior. 

The  peritoneum  covers  the  entire  posterior  surface  of  the 
uterus,  except  the  vaginal  portion  of  the  cervix,  and  extends 
down  over  the  posterior  vaginal  wall  for  about  J  inch,  forming 
Douglas's  pouch  (recto-vaginal  or  recto-genital  pouch),  after 
which  it  is  reflected  on  to  the  rectum.  In  front  it  extends  down 
to  the  junction  of  the  body  and  cervix,  and  is  then  reflected 
on  to  the  bladder.  Laterally,  the  peritoneum  extends  out 
from  the  uterus  in  a  double  layer  to  the  pelvic  wall,  constituting 
the  broad  ligament,  while  a  small  fold,  called  the  sacro-genital 
fold,  extends  on  either  side  from  the  posterior  wall  of  the 
cervix  to  the  side  of  the  sacrum.  These  latter  folds  contain 
connective  tissue  and  unstriped  muscular  fibres,  and  form 
lateral  boundaries  to  Douglas's  pouch.  The  uterus  possesses 
a  large  range  of  movement,  rising  and  falling  according  to  the 
condition  of  the  bladder,  lying  frequently  a  little  to  one  side 
of  the  middle  line,  especially  to  the  right,  while  on  bimanual 
examination  it  may  be  moved  through  a  considerable  area 
without  causing  pain.  As  the  cervix  is  more  fixed  than  the 
fundus,  the  organ  is  frequently  flexed  at  the  junction  of  these 
parts,  and  this  flexion  may  be  pathological  and  either  anterior 
(anteflexion)  or  posterior  (retroflexion) .  Retroversion  of  the 
whole  organ  may  also  occur,  and  likewise  prolapse,  or 
procidentia,  where  the  organ  descends  through  the  vagina, 
which  is  turned  inside  out.  the  bladder  frequently  being 

18— 2 


276  SURGICAL  ANATOMY 

directed  downwards  also,  while  the  ureters  become  dilated 
in  consequence  of  obstruction. 

The  CAVITY  OF  THE  UTERUS  normally  is  practically  a  tri- 
angular slit,  whose  apex  is  at  the  internal  os,  and  whose  basal 
angles  correspond  to  the  uterine  ostia  of  the  Fallopian  tubes, 
while  the  cervical  canal  is  spindle-shaped,  wider  at  the  centre 
than  at  either  extremity,  its  mucous  membrane  being  thrown 
into  folds  radiating  upwards  and  outwards  from  the  middle 
line  in  front  and  behind  (arbor  vitse).  Inflammation  of  the 
uterus,  metritis,  frequently  gives  rise  to  pelvic  cellulitis 
(parametritis),  large  abscesses  occurring  in  the  parametrium 
(q.v.),  which,  if  untreated,  may  burst  into  the  vagina  or  point 
above  Poupart.  The  veins  also  may  become  affected,  causing 
thrombosis,  which  may  extend  to  the  internal  and  even  common 
iliac  veins.  In  such  cases  swelling  of  the  whole  lower  limb 
(phlegmasia  alba  dolens)  occurs,  and  pyaemia  may  also  be  set 
up.  Pelvic  peritonitis  (perimetritis)  may  be  caused  by  ex- 
tension of  septic  matter  from  the  interior  of  the  uterus  along 
the  Fallopian  tubes. 

Carcinoma  frequently  occurs  in  the  cervix,  spreads  thence 
locally,  involving  the  parametrium,  ureters,  bladder,  and 
rectum,  and  later  by  the  lymphatics.  Fibro-myoma  of  the 
uterus  is  very  common,  and  frequently  attains  a  large  size. 
Such  tumours  are  classified  according  to  their  position  as 
submucous,  interstitial,  and  subperitoneaL  Removal  of 
the  uterus  may  be  accomplished  through  the  abdomen 
(abdominal  hysterectomy]  or  through  the  vagina  (vaginal 
hysterectomy).  In  the  former  a  median  vertical  abdominal 
incision  is  made,  the  broad  ligaments  ligatured  and  cut,  the 
vagina  cut  through,  and  the  uterus  with  its  appendages  re- 
moved. Care  must  be  taken  to  avoid  the  ureters.  In  vaginal 
hysterectomy,  the  uterus  is  drawn  down,  the  vagina  divided, 
the  bladder  reflected,  the  broad  ligaments  drawn  down  and 
ligatured  in  detachments,  and  the  uterus  finally  removed. 
Care  is  here  especially  necessary  to  avoid  the  ureters. 
Anteriorly,  the  uterus  is  related  to  the  utero-vesical  pouch 
of  the  peritoneum  down  almost  to  the  cervix,  and  below  this, 
for  fully  f  inch,  is  loosely  attached  to  the  posterior  bladder 
wall  by  connective  tissue  ;  posteriorly  to  the  pelvic  colon  and 
small  intestine,  except  when,  the  rectum  and  bladder  being 
distended,  these  coils  are  displaced  upwards  and  the  rectum 


THE  PELVIS  277 

itself  forms   the  posterior  relation.     Laterally,  the  uterus  is 
related  to  the  broad  ligaments  and  ureters. 

The  uterine  artery,  from  the  anterior  division  of  the  internal 
iliac  or  one  of  its  larger  branches,  descends  on  the  lateral  pelvic 
wall  in  front  of  the  ureter,  runs  inward  in  the  parametrium, 
crossing  the  ureter  above  th:  lateral  vaginal  fornix,  and  then 
turns  up  along  the  lateral  border  of  the  uterus,  until,  at  the 
level  of  the  ovarian  ligament,  it  divides  into  its  terminal 
branches.  In  its  upward  course  the  artery  is  very  tortuous, 
and  gives  off  many  branches,  which  anastomose  with  those 
from  the  opposite  side,  and  with  branches  from  the  ovarian 
artery,  while  its  branch  to  the  ovary  anastomoses  with  the 
ovarian  artery,  and  that  to  the  round  ligament  with  the  deep 
epigastric  artery.  The  uterus  is  also  supplied  by  the  uterine 
branch  of  the  ovarian  artery.  The  vessels  in  the  uterine  wall 
run  transversely  to  the  length  of  the  organ.  Ligature  of  the 
uterine  artery  has  been  done  in  the  hope  of  arresting  the 
growth  of  a  uterine  tumour.  The  uterine  veins  are  thin- walled, 
and  originate  in  cavernous  spaces  in  the  middle  coat  of  the 
uterus,  whence,  emerging  chiefly  about  the  cervix,  they  unite 
with  those  from  the  vagina  to  form  the  utero-vaginal  plexus, 
which  surrounds  the  ureter.  Thence  the  blood  is  conveyed 
in  two  large  veins,  one  on  either  side  of  the  ureter,  which 
ultimately  unite  and  terminate  in  the  internal  iliac.  During 
pregnancy  these  vessels  are  greatly  increased  in  size.  The 
lymphatics  are  arranged  in  three  groups,  in  the  mucous 
membrane,  muscular  coat,  and  subperitoneal  tissue.  They 
emerge  chiefly  about  the  level  of  the  cervix,  and  join  the  glands 
about  the  bifurcation  of  the  common  iliac  artery,  while  a 
few  from  the  body  of  the  uterus  pass  up  with  the  ovarian 
vessels  to  the  lumbar  glands  arranged  along  the  aorta,  and 
others  pass  to  the  inguinal  glands  along  the  round  ligament. 
The  nerve-supply  of  the  uterus  is  from  the  second  to  fourth 
sacral  nerves,  while  sympathetic  fibres  reach  it  from  the 
hypogastric  plexus  running  in  the  utero-sacral  folds. 

The  VAGINA  leading  from  the  cervix  to  the  vulva  is  about 
3  inches  long,  and  is  partially  occluded  at  its  lower  extremity 
in  nulliparae  by  a  fold  of  mucous  membrane  called  the  hymen 
It  is  directed  downwards  and  forwards,  is  slightly  curved 
with  the  convexity  backwards,  and  is  related  in  front  to  the 
bladder  and  urethra,  and  to  Douglas's  pouch  and  rectum 


2/8 


SURGICAL  ANATOMY 


behind.  It  will  be  remembered  that  the  cervix  uteri  is  in- 
vaginated  into  the  vagina,  and  the  mucous  membrane  being 
reflected  from  the  one  to  the  other  forms  vaginal  fornices, 
or  recesses,  anterior,  posterior,  and  lateral.  In  nulliparae 
the  mucous  membrane  is  thrown  into  transverse  folds — vagina! 
ruga.  These  frequently  make  it  difficult  to  remove  pyogenic 


FIG.  34. — VIEW  OF  FEMALE  PELVIC  BASIN  FROM  ABOVE. 
(After  Testut.) 


1.  Rectum. 

2.  Uterus. 

3.  Bladder. 

4.  Urachus. 

5.  Common  iliac  artery, 

6.  Common  iliac  vein. 


7.  Ureter. 

8.  Uterine  vessels. 

9.  External  iliac  artery. 

10.   Fallopian  tube  and  ovary, 
n.  Lower    margin    of    broad 
ligament. 


12.  Round  ligament. 

13.  Obliterated     hypogastric 

artery. 

14.  Plica  transversa  vesica?. 

15.  Paravesical  fossa. 

16.  Pararectal  fossa. 


infection  (e.g.,  gonorrhoea),  and  by  direct  extension,  endome- 
tritis  may  follow  vaginitis.  Owing  to  the  angularity  of  the 
junction  of  uterus  and  vagina,  the  vagina  lying  almost  parallel 
to  the  pelvic  brim,  the  anterior  vaginal  wall  only  measures 
a  little  over  2  inches,  whereas  the  posterior  measures  3  inches. 
In  front  the  vagina  is  but  loosely  attached  to  the  trigonal 


THE  PELVIS  279 

area  of  the  bladder,  but  is  firmly  connected  with  the  urethra. 
Vaginal  cystotomy  or  urethrotomy  is  sometime^  performed 
througM  this  anterior  wall.  Posteriorly,  it  is  only  separated 
from  the  rectal  ampulla  by  a  thin  layer  of  connective  tissue 
(recto-vaginal  septum),  but  lower  down  it  is  considerably 
separated  from  th^  anal  canal  by  a  dense  mass  of  connec- 
tive and  fatty  tissue  called  the  perineal  body.  Laterally, 
it  is  related  to  the  parametrium,  vaginal  plexus  of  veins, 
ureter,  and  levator  ani  muscle.  Occasionally,  by  yielding  of 
some  portion  of  the  vaginal  wall,  a  protrusion  of  bladder, 
rectum  or  small  intestine  may  occur  into  the  vagina,  producing 
a  vaginal  cystocele,  rectocele  or  enterocele,  and  vaginal  wounds 
have  opened  into  the  peritoneal  cavity,  allowing  the  escape 
of  small  intestine.  The  vaginal  wall  may  be  evaginated  for 
examination  by  a  finger  in  the  rectum.  Vesico- vaginal 
and  recto-vaginal  fistulce  occur  not  infrequently,  owing  to  the 
thinness  of  the  vaginal  walls.  The  vaginal  walls  are  very 
vascular  and  dilatable,  as  is  evidenced  at  the  puerperium 
and  in  cases  of  retained  menses.  The  narrowest  part  is  the 
vaginal  outlet,  surrounded  by  the  sphincter  vaginae  muscle, 
and  here  laceration  frequently  occurs.  A  spasmodic  con- 
traction of  the  sphincter  muscle — -vaginismus — is  sometimes 
met  with.  The  vagina  is  supplied  by  branches  of  the  vesico- 
vaginal  artery  of  the  anterior  division  of  the  internal  iliac 
artery,  and  vaginal  branches  of  the  uterine  and  middle  haemor- 
rhoidal  arteries,  and  branches  of  the  internal  pudic.  The 
ve  ns  form  a  plexus  round  the  vagina,  and  drain  into  the 
tributaries  of  the  internal  iliac.  The  lymphatics  from  the 
upper  part  join  the  internal  iliac  group,  and  those  from  the 
lower  part  join  the  superficial  inguinal  glands.  The  nerves 
are  derived  from  the  third  and  fourth  sacral  and  utero- 
vaginal  and  vesical  plexuses. 

The  Mullerian  ducts  of  the  embryo  unite  at  a  very  early 
period  at  their  lower  extremities  to  form  the  vagina  and 
uterus,  while  their  upper  extremities,  which  open  into  the 
peritoneal  cavity,  form  the  Fallopian  tubes.  From  imperfect 
fusion  of  these  ducts  a  double  uterus  (uterus  bicornis)  may 
arise,  while,  if  the  condition  extend  to  the  vagina,  a  septum 
may  present,  partially  dividing  the  vagina  into  two  compart- 
ments. 

The  broad  ligaments  form   a  transverse  partition  of  the 


28o  SURGICAL  ANATOMY 

pelvic  basin,  inclined  forwards  at  their  uterine,  but  more 
vertically  at  their  pelvic  extremities,  and  contain  between 
their  layers  ovary,  ovarian  ligament,  Fallopian  tube,  round 
ligament,  uterine,  and  ovarian  vessels,  nerves,  and  lymphatics, 
parametrium  (consisting  of  muscular  and  fatty  connective 
tissue),  and  vestigial  remains.  Quadrilateral  in  outline,  the 
inner  border  is  attached  to  the  uterine  body,  supravaginal 
cervix,  and  lateral  vaginal  fornix  ;  the.  outer  border  is 
attached  to  the  p?lvic  wall,  extending  from  the  external 
iliac  vessels  and  inner  border  of  the  psoas  above,  to  the  pelvic 
floor  below,  crossing  the  obturator  fossa  in  its  course.  The 
upper  border  is  free,  and  corresponds  to  the  Fallopian  tube 
in  the  greater  part  of  its  course,  and  the  lower,  narrow  border 
is  separated  from  the  pelvic  floor  by  connective  tissue,  con- 
taining ureter  and  uterine  veins.  The  anterior  surface, 
directed  downwards  and  forwards,  overlies  the  bladder ; 
the  posterior  surface  is  related  to  the  intestine. 

Occupying  the  upper  border  of  the  ligament,  the  FALLOPIAN 
TUBE  runs  upwards  and  outwards  and,  arching  round,  ends 
in  the  fimbriated  extremity  which  is  attached  to  the  upper  pole 
of  the  ovary  by  one  long  fimbria — the  ovarian  fimbria.  The 
tube  is  over  4  inches  long,  and  its  canal  is  very  narrow, 
averaging  £  inch  in  diameter.  The  portion  immediately 
beyond  the  uterine  wall  is  called  the  isthmus,  and  the  remainder 
the  ampulla.  It  opens  at  its  fimbriated  extremity  into  the 
peritoneal  cavity  by  a  funnel-shaped  expansion  called  the 
infundibiilum,  \  inch  wide,  which  lodges  the  abdominal 
ostium  T^  inch  in  diameter ;  and  into  the  uterus  at  its  upper 
and  outer  part  by  a  minute  orifice  ^  inch  in  diameter.  The 
two  openings  are  called  the  abdominal  and  uterine  ostia, 
and  thus  the  tube  provides  a  direct  communication  between 
the  peritoneal  cavity  and  that  of  the  uterus.  The  broad 
ligament  surrounding  the  tube  is  frequently  called  the  meso- 
salpinx,  and  both  tube  and  mesosalpinx  are  frequently  folded 
back  over  the  upper  extremity  of  the  ovary,  forming  a  recess, 
which  has  been  called  the  bursa  ovarii.  Beyond  the  fimbriated 
extremity  of  the  tube,  a  triangular  process  of  the  peritoneum 
of  the  upper  border  of  the  broad  ligament  runs  up  to  the 
external  iliac  vessels,  and  encloses  the  ovarian  vessels,  nerves, 
and  lymphatics.  This  process  is  called  the  suspensory 
ligament  of  the  ovary. 


THE   PELVIS  281 

Salpingitis,  or  inflammation  of  the  tube,  is  due  to  infection 
travelling  to  it  from  the  uterus — frequently  gonorrhceal.  In 
such  oases  the  abdominal  ostium  may  become  sealed  by 
adhesions,  and  the  tube,  dilated  with  pus,  presents  a 
sausage -like  swelling  (pyosalpinx) .  The  tube  may  also 
become  distended  with  clear  fluid  (hydrosalpingitis)  in  catarrhal 
conditions,  or  with  blood  (hamosalpingitis] .  On  the  other 
hand,  infective  matter  may  escape  into  the  peritoneal  cavity, 
causing  a  pelvic  peritonitis.  Such  peritonitis  generally  remains 
localized  by  many  adhesions  to  surrounding  parts.  Where 
the  ovum  after  impregnation  becomes  fixed  in  the  tube,  a 
tubal  pregnancy  occurs,  the  tube  generally  rupturing  between 
the  seventh  and  twelfth  week,  and  frequently  causing  fatal 
haemorrhage.  The  tortuous  condition  of  the  tube  and  the 
folds  of  its  mucous  membrane  may  be  causes  of  obstruction 
to  the  passage  of  the  ovum. 

The  OVARY,  ovoid  in  shape  and  about  ij  inches  long  by 
\  inch  broad  at  its  widest  part,  is  situated  nearly  vertically, 
its  upper  pole  being  attached  to  the  pelvic  brim  by  the  sus- 
pensory ligament,  while  the  lower  pole  is  connected  to  the 
uterus  by  the  ligament  of  the  ovary,  which  consists  of  a  rounded 
nbro-muscular  band,  slightly  over  i  inch  in  length,  which 
is  attached  to  the  uterus  just  below  and  behind  the  point  of 
entrance  of  the  Fallopian  tube.  The  outer  end  of  the  Fallopian 
tube  arches  round  the  upper  pole  of  the  ovary,  to  which  the 
ovarian  nmbria  is  frequently  attached.  Instead  of  lying 
directly  in  the  plane  between  the  layers  of  the  triangular 
ligament,  the  ovary  forms  a  projection  on  the  posterior 
wall,  pushing,  of  course,  the  posterior  layer  of  the  broad 
ligament  before  it  as  it  does  so,  and  thus  forming  a  short 
mesentery,  the  mesovarium.  Thus  the  ovary  is  said  to  possess 
a  posterior  free  border  (covered,  however,  by  altered  peri- 
toneum), and  an  anterior  border  to  which  the  two  layers  of 
the  mesovarium  are  attached,  and  between  the  layers  of 
which  the  ovarian  vessels  and  nerves  with  some  connective 
tissue  and  muscular  fibres  run.  The  ovary  thus  projecting 
from  the  posterior  layer  of  the  broad  ligament  is  frequently 
accommodated  in  a  depression  in  the  pelvic  peritoneum  lining 
the  posterior  part  of  the  obturator  fossa,  to  which  the  name 
'  ovarian  fossa  '  is  given.  This  fossa  lies  between  the  ob- 
literated hypogastric  artery  in  front  and  ureter  and  uterine 


282  SURGICAL  ANATOMY 

vessels  behind,  which  thus  form  relations  of  the  ovary,  while 
above  the  ovary  lie  the  external  iliac  vessels,  and  below,  the 
peritoneum  covering  the  pelvic  floor.  The  ovary  may  be 
palpated  by  the  fore  and  middle  finger  of  one  hand  in  the 
posterior  cul-de-sac  of  vagina  pressing  up  and  outwards,  and 
the  fingers  of  the  other  hand  flat  above  the  centre  of  Poupart 
pressing  downwards.  The  ovary  seldom  leaves  its  normal 
position,  save  in  uterine  displacements,  or  when  affected  by 
tumour.  Occasionally,  it  becomes  prolapsed,  and  may  occur 
in  hernia. 

Ovarian  tumours  are  most  frequently  cystic,  and  generally 
originate  from  the  cortical  zone  in  the  region  of  the  Graafian 
follicles.  Such  tumours  frequently  attain  an  enormous  size,  and 
have  a  pedicle  composed  of  ovarian  ligament,  Fallopian  tube, 
broad  ligament,  etc.  Dermoids  occasionally  occur,  as  also  sar- 
comata. Removal  of  the  ovary,  or  ovariotomy,  is  necessitated  in 
such  cases,  the  pedicle,  which  contains  many  large  vessels,  being 
carefully  ligatured.  Removal  has  also  been  suggested  in  car- 
cinoma mammae  as  likely  to  retard  the  growth,  but  has  not 
proved  successful. 

The  peritoneum  covering  the  surface  of  the  ovary  is 
altered,  being  nodular  and  covered  by  a  layer  of  columnar 
cells.  The  ovary  is  supplied  with  blood  by  the  ovarian 
artery — a  branch  of  the  aorta— and  by  the  ovarian  branch 
of  the  uterine  artery,  both  of  which  pass  to  the  ovary 
along  the  mesovarium.  The  ovarian  veins  emerge  by  the 
mesovarium,  and  form  a  plexus  between  the  layers  of  the 
mesosalpinx.  The  lymphatics  ascend  by  the  suspensory 
ligament  of  the  ovary  to  the  lumbar  glands,  and  the  nerves 
are  derived  from  the  tenth  dorsal  segment  of  the  cord  through 
the  ovarian  plexus  (a  branch  of  the  aortic  plexus),  and  some 
branches  of  the  uterine  plexus. 

The  HYDATIDS  OF  MoRGAGNi  are  small  pedunculated  cystic 
structures  near  the  infundibulum  of  the  Fallopian  tube. 
One  or  more  in  number,  they  are  supposed  to  represent  the 
upper  end  of  the  Wolffian  duct.  Situated  between  the  layers 
of  the  mesosalpinx  and  in  its  outer  one-third,  lying  between 
the  Fallopian  tube  and  the  ovary,  is  the  parovarium  (organ  of 
Rosenmuller) .  This  consists  of  over  half  a  dozen  tubes,  lined 
with  ciliated  epithelium,  one  of  which,  running  parallel  to 
the  Fallopian  tube,  is  called  the  duct  of  Gartner,  and  represents 


THE  PELVIS  283 

the  Wolffian  duct.  The  remainder  are  homologous  with  the 
male  vasa  efferentia  and  epididymis.  Also  lying  between 
the  layers  of  the  mesosalpinx,  but  internal  to  the  parovarium, 
is  the  paroophoron.  This  consists  in  infancy  of  a  series  of 
coiled  tubes,  representing  the  mesonephros,  and  is  homologous 
with  the  paradidymis  of  the  male. 

Parovarian  cysts  may  arise  from  either  the  parovarium  or 
paroophoron.  They  occur  between  the  layers  of  the  broad 
ligament,  and  are  generally  unilocular  and  filled  with  clear  fluid. 

The  ROUND  LIGAMENT,  a  fibro-muscular  band  nearly  6  inches 
in  length,  extends  from  the  lateral  angle  of  the  uterus  in  front, 
and  a  little  below  the  opening  of  the  Fallopian  tube,  horizon- 
tally outwards  between  the  layers  of  the  broad  ligament  to  the 
lateral  pelvic  wall,  whence  it  is  directed  upwards  and  forwards 
to  the  trigonum  femorale,  and,  curving  round  the  deep  epi- 
gastric artery,  enters  the  internal  abdominal  ring.  In  its 
pelvic  stage  it  crosses  the  obturator  vessels  and  nerve,  obliter- 
ated hypogastric  artery,  and  external  iliac  vessels,  and  in  the 
inguinal  canal  it  is  accompanied  by  the  ilio-inguinal  nerve,  a 
process  of  transversalis  fascia,  and  sometimes  by  a  process  of 
peritoneum  called  the  canal  of  Nuck.  It  ends  in  the  sub- 
cutaneous tissue  and  skin  of  the  labium  majus.  The  presence 
of  the  canal  of  Nuck  predisposes  to  congenital  inguinal  hernia, 
and  occasionally  it  may  become  distended  with  fluid,  causing 
a  hydrocele  of  the  canal  of  Nuck.  The  round  ligaments  are 
sometimes  shortened  in  order  to  correct  retroversion  or  flexion 
of  the  uterus  (Alexander's  operation) .  This  is  done  by  exposing 
them  at  the  external  abdominal  ring,  pulling  the  anterior 
portions  forwards  on  both  sides,  and  fixing  them  to  the  parietes. 

The  lower  subdivision  of  the  broad  ligament,  that  below  the 
line  of  attachment  of  the  mesovarium,  is  called  the  MESO- 
METRIUM,  and  becomes  thick  as  it  approaches  the  pelvic  floor. 
Ultimately  the  peritoneum  of  the  anterior  layer  is  reflected 
on  to  the  lateral  pelvic  wall  and  bladder,  while  posteriorly  on 
either  side  it  forms  the  sacro-genital  fold  (these  folds  being 
connected  by  a  ridge  on  the  posterior  wall  of  the  cervix,  called 
the  torus  uterinus),  and  thence  gains  the  lateral  and  posterior 
pelvic  walls.  The  extraperitoneal  tissue  situated  on  either 
side  of  the  cervix  and  upper  part  of  the  vagina,  and  which  is 
continued  for  a  considerable  distance  between  the  layers  of 
the  broad  ligament,  and  is  continuous  with  the  extraperitoneal 


284  *l'KC,ICAL  ANATOMY 

tissue  lining  the  lateral  pelvic  wall,  etc.,  is  called  the  PARA- 
METRIUM.  In  it  run  the  uterine  vessels,  nerves,  and  lym- 
phatics, and  the  ureter. 

The  URETER  runs  from  the  sacro-iliac  articulation  down  and 
backwards  to  near  the  floor  of  the  lateral  pelvic  wall,  whence 
it  enters  the  broad  ligament.  This  portion  is  3  inches  long, 
and  lies  first  in  front  of,  or  to  the  inner  side  of,  the  internal 
iliac  vessels  ;  then  forms  the  posterior  boundary  of  the  obtu- 
rator fossa,  and  lies  immediately  behind  the  ovary.  The 
second  portion,  2  inches  long,  traverses  the  parametrium 
between  the  layers  of  the  broad  ligament,  J  inch  above  the 
lateral  vaginal  fornix,  and  separated  from  the  supravaginal 
cervix  by  J  inch.  Here  it  is  closely  enveloped  in  the  venous 
plexuses,  and  is  crossed  above  by  the  uterine  artery.  Thence 
it  converges  towards  its  neighbour  of  the  other  side,-  so  that  it 
is  even  nearer  the  cervix  in  front  than  laterally  (and  may  be 
detected  by  palpation  from  the  vagina),  to  enter  the  bladder 
at  the  basal  angle  of  the  trigone  i  inch  below  the  level  of  the 
external  os,  and  just  above  the  roof  of  the  vagina,  its  course 
through  the  bladder  wall  being  very  oblique,  and  measuring 
|  inch  in  length. 

The  term  VULVA  is  applied  to  the  female  external  genitals, 
including  the  labia  majora  and  minora,  clitoris,  urethral  and 
vaginal  openings.  The  urethral  orifice  is  immediately  in  front 
of  that  of  the  vagina,  and  an  inch  behind  the  clitoris,  and  is 
surrounded  by  slightly  prominent  margins.  The  vaginal 
opening  is  partially  closed  in  the  young  by  the  hymen,  and 
when  this  is  imperf orate,  as  it  occasionally  is,  retention  of  the 
menses  occurs.  Bartholins  glands  (equivalent  to  Cowper's),  each 
about  the  size  of  a  small  bean,  are  situated  low  down  on  the 
lateral  wall  of  the  vagina,  and  open  by  slender  ducts  in  the 
angle  between  the  vagina  and  labium  minus.  Cystic  dilata- 
tion, or  even  abscess  of  the  duct,  may  occur.  The  labia  majora 
are  similar  to  the  scrotum  in  nerve  and  blood  supply  and 
pathological  tendencies.  They  may  become  very  cedematous, 
or  present  large  extravasations  of  blood,  and  may  be  affected 
by  elephantiasis. 

The  PERINEUM  is  a  lozenge-shaped  area,  nearly  4  inches 
long  and  3j  inches  broad  at  the  widest  part,  which  corresponds 
to  the  outlet  of  the  pelvis,  being  bounded  in  front  by  the 


THE  PELVIS  285 

symphysis  ;  laterally  by  the  rami  of  the  pubes  and  ischium, 
tuber  ischii,  and  great  sacro-sciatic  ligament  ;  posteriorly  by 
the  coccyx.  Above  it  is  separated  from  the  pelvis  by  the 
pelvic  diaphragm,  consisting  of  the  levator  ani  and  coccygei 
muscles,  which  are  covered  on  their  pelvic  aspect  by  the  recto- 
vesical  fascia,  and  on  their  perineal  aspect  by  the  anal  fascia. 
These  muscles,  originating  from  a  line  extending  from  near 
the  lower  border  of  the  symphysis  to  the  ischial  spine,  slope 
down  and  inwards  to  meet  one  another  in  the  middle  line, 
leaving,  however,  passages  for  urethra  and  rectum,  and,  in 
addition  (in  the  female),  for  the  vagina.  As  the  muscles  thus 
diverge  from  the  pelvic  wall,  they  leave  a  lateral  space  on 
either  side,  which  they,  covered  by  anal  fascia,  bound  on  the 
inner  side,  and  which  is  bounded  externally  by  the  pelvic 
parietes,  covered  by  obturator  fascia,  called  the  ischio-rectal 
fossa  (see  Figs.  29,  30,  and  31).  The  perineum  is  subdivided 
into  an  anterior  urogenital  and  a  posterior  rectal  triangle  by  a 
transverse  line  crossing  the  mid-point  of  the  perineum  about 
i  inch  in  front  of  the  anus,  and  a  little  in  front  of  the  tuber 
ischii. 

The  UROGENITAL  SPACE  forms  practically  an  equilateral 
triangle,  whose  sides  are  about  3^  inches  in  length,  and 
it  is  bounded  on  its  deep  surface  by  the  triangular  ligament. 
The  skin  and  superficial  fascia  do  not  call  for  special 
comment,  but  the  deep  layer  of  superficial  fascia — Colles's 
fascia — has  an  important  surgical  bearing.  Attached  later- 
ally to  the  rami  of  the  pubes  and  ischium,  COLLES'S  FASCIA, 
which  is  of  a  membranous  structure,  dips  down  posteriorly, 
and  becomes  continuous  with  the  base  of  the  triangular 
ligament,  while  anteriorly  it  is  continuous  with  the  dartos 
coat  of  the  scrotum  and  fascia  of  the  penis,  and,  con- 
tinuing up  in  front  of  the  spermatic  cord,  becomes  con- 
tinuous with  the  deep  layer  of  the  superficial  fascia  of  the 
abdomen  (Scarpa's  fascia).  Thus  the  structures  contained  in 
the  urogenital  triangle  are  contained  in  a  space  which  is  closed, 
except  in  front,  by  Colles's  fascia  superficially,  and  the  tri- 
angular ligament  deeply.  When,  therefore,  on  rupture  of  the 
urethral  bulb  which  lies  in  this  space,  extravasation  of  urine 
occurs,  the  urine  is  forced  to  come  forward,  distending  the 
scrotum  and  penis,  and  finding  its  way  up  in  front  of  the  cord 
to  the  front  of  the  abdomen. 


286  SURGICAL  ANATOMY 

As  a  result  of  gonorrhceal  infection  of  the  urethra,  peri- 
urethral  abscess  is  apt  to  occur  in  this  region,  and  may 
burrow  ultimately  to  the  surface  and  discharge.  If  it  also 
communicates  with  the  urethra,  a  perineal  urinary  fistula 
would  result.  •  Extravasation  may  also  cause  such  a  fistula. 
Situated  in  the  middle  line  of  the  triangle  is  the  bulb 
of  the  corpus  spongiosum,  enclosing  the  urethra,  and  sur- 
rounded by  the  accelerator  urinae  muscle,  while  lying  along 
the  rami  of  the  pubes  and  ischium  on  either  side  are  the  crura 
of  the  corpora  cavernosa,  which  converge  to  meet  the  corpus 
spongiosum  under  the  pubic  arch,  and  form  the  body  of  the 
penis.  Thus,  the  urogenital  triangle  is  divided  into  two  smaller 
triangles,  the  corpus  spongiosum  forming  the  inner  side 
common  to  both,  the  crura  forming  the  outer  sides  of  the  two 
triangles,  while  the  transversus  perinaei  muscles  converging 
to  the  central  point  of  the  perineum  from  the  rami  of  the 
ischium  form  the  third  sides.  The  space  is  traversed  from 
behind  forwards  by  the  superficial  perineal  vessels  and  nerves 
(from  the  internal  pudic  arterial  and  venous  trunks),  which 
enter  it  by  piercing  the  base  of  the  triangular  ligament.  The 
transverse  perineal  arteries  (internal  pudic)  also  pierce  the 
triangular  ligament,  and  accompany  the  muscles  of  that 
name,  while  the  long  pudendal  nerve  (small  sciatic)  enters  the 
space  through  Colles's  fascia. 

The  CENTRAL  POINT  OF  THE  PERINEUM  lies  about  a  finger- 
breadth  in  front  of  the  anus,  and  at  it  the  antero-posterior 
accelerator  urinae  and  sphincter  ani,  and  the  lateral  trans- 
versus perinaei  muscles  meet.  Further,  it  marks  the  centre 
of  the  base  of  the  triangular  ligament,  and  it  is  used  as 
a  landmark  in  certain  operations,  the  incisions  not  being 
carried  beyond  it  in  order  to  avoid  injury  to  the  bulb,  which 
lies  just  in  front  of  it. 

The  floor  of  the  triangle  is  formed  by  the  TRIANGULAR 
LIGAMENT,  which  is  composed  of  two  layers,  enclosing 
certain  structures,  the  anterior  layer  being  equivalent  to 
the  deep  perineal  fascia,  while  the  deep  or  posterior  layer 
is  derived  from  the  obturator  layer  of  pelvic  fascia.  Attached 
laterally  to  the  pubic  arch,  the  layers  of  the  triangular 
ligament  join  one  another  at  the  base  of  the  triangle, 
which  is  about  ij  inches  deep.  The  anterior  layer  presents 
a  small  opening  at  the  apex,  under  the  pubic  arch,  through 


THE  PELVIS  287 

which  the  dorsal  vessels  of  the  penis  pass.  Between  the 
layers  of  the  triangular  ligament  is  the  membranous  urethra, 
surrounded  by  the  compressor  urethrae.  This  lies  about 
i  inch  below  the  symphysis,  and  f  inch  above  the  central 
point.  When  ruptured,  as  by  a  blow  in  the  perineum,  extrava- 
sation takes  place  between  the  layers  of  the  triangular  liga- 
ment, by  which  it  is  limited  at  first.  The  anterior  layer  of  the 
ligament  is  pierced  by  the  artery  to  the  bulb,  close  to  the 
urethra,  and  by  the  artery  to  the  corpus  cavernosum  near 
the  subpubic  angle.  In  addition  to  the  membranous  urethra 
and  compressor  muscle,  there  are,  between  the  layers  of  the 
triangular  ligament,  the  termination  of  the  internal  pudic 
artery,  dividing  into  dorsal  artery  of  penis  and  artery  of  the 
corpus  cavernosum,  artery  to  the  bulb,  Cowper's  gland,  and 
the  dorsal  vein  and  nerve  of  the  penis.  Lying  on  the  deep 
surface  of  the  deep  layer  of  the  triangular  ligament  is  the 
prostate  gland,  surrounded  by  its  capsule,  derived  from  recto- 
vesical  layer  of  pelvic  fascia,  prostatic  plexus,  etc.  In  cutting 
down  on  the  prostate  through  the  perineum,  seven  layers  of 
alternate  fascia  and  muscle  are  met  with  :  (i)  Superficial 
fascia  ;  (2)  superficial  perineal  muscles  ;  (3)  anterior  layer  of 
triangular  ligament ;  (4)  compressor  urethrae  muscle ;  (5)  pos- 
terior layer  of  triangular  ligament ;  (6)  levator  ani  muscle  ; 
(7)  prostatic  capsule. 

Perineal  lithotomy — to  remove  a  stone  from  the  bladder, 
which  here  lies  at  a  depth  of  3  inches — is  an  operation  seldom 
performed.  It  may  be  either  lateral  or  median.  In  the  lateral 
operation  an  incision  2\  inches  long  is  made,  commencing 
just  to  the  left  and  behind  the  central  point  of  the  perineum, 
and  carried  down  and  outwards  into  the  ischio-rectal  fossa, 
to  end  at  the  junction  of  the  outer  and  middle  one-third  of  a 
line  joining  the  tuber  ischii  and  the  anus.  In  addition  to 
skin  and  superficial  fascia,  the  transversus  perinei  muscle, 
artery,  and  nerve,  lower  edge  of  external  layer  of  triangular 
ligament,  and  external  hsemorrhoidal  vessel  and  nerves  are 
cut.  The  scalpel  is  now  entered  through  the  exposed  mem- 
branous urethra,  and  its  point  engaged  in  the  groove  of  the 
staff,  while  the  edge  is  directed  toward  the  left  tuber  ischii, 
and  in  this  position  it  is  pushed  along  the  groove  into  the 
bladder.  In  this  incision  the  membranous  and  prostatic 
portions  of  the  urethra,  posterior  layer  of  the  triangular  liga- 


288  SURGICAL  ANATOMY 

ment,  compressor  urethrae,  and  anterior  fibres  of  the  levator 
ani,  and  left  lateral  lobe  of  the  prostate  are  divided.  In  the 
first  incision  of  this  operation  the  bulb  may  be  wounded  if  the 
incision  be  begun  too  far  forward,  or  the  staff  is  not  drawn 
sufficiently  up  under  the  pubes.  The  rectum  may  be  cut  if  the 
incision  is  carried  too  far  back  or  the  viscus  is  distended,  and 
the  pudic  vessels  might  be  damaged  if  the  incision  were  carried 
right  to  the  ramus.  In  the  second  incision  the  prostatic  cap- 
sule and  plexus  of  veins  are  necessarily  cut ;  but  if  the  incision 
be  carried  too  far  forward,  the  visceral  layer  of  the  pelvic 
fascia  might  be  cut,  and  the  pelvic  cavity  opened  ;  this  is  more 
likely  to  occur  in  children,  where  the  prostate  is  rudimentary. 

In  median  lithotomy  (Cock's  operation)  the  knife  is  entered  in 
the  middle  line  just  in  front  of  the  anus,  and  is  directed  to 
enter  the  median  groove  on  the  staff  at  the  apex  of  the  prostate, 
the  membranous  urethra  being  incised  in  withdrawing  the 
knife,  a  wound  i  J  inches  long  being  made  in  the  median  raphe. 
The  finger  is  now  introduced,  the  parts  dilated,  and  the  stone 
removed.  Here  the  parts  divided  are  skin  and  superficial 
fascia,  sphincter  ani,  central  point  of  perineum,  base  of  the 
triangular  ligament,  the  whole  length  of  the  membranous 
urethra,  and  compressor  urethrae.  As  this  operation  is  made 
through  the  avascular  raphe,  there  is  little  bleeding,  and  the 
pelvic  fascia  is  less  likely  to  be  opened  by  the  dilating  process  ; 
on  the  other  hand,  the  space  obtained  is  small,  the  bulb  is  apt 
to  be  wounded  (but  median  wounds  of  the  bulb  do  not  bleed 
much),  and  in  children  the  process  of  separation  would  be 
very  apt  to  tear  the  bladder  from  the  urethra.  Similar  opera- 
tions may  be  performed  for  removal  of  the  prostate  by  the 
perineal  route,  or  for  making  a  simple  incision  into  the  bladder 
to  afford  free  drainage  in  critical  cases  of  enlarged  prostate. 
The  pudic  nerve  supplies  sensation  to  the  skin  of  the  perineum 
and  also  of  the  penis,  scrotum,  and  anus,  while  it  also  supplies 
the  mucous  membrane  of  the  urethra  and  muscles  of  the  penis. 
Thus,  painful  affections  of  the  perineum  and  anus  may  cause 
priapism.  The  perineal  branch  of  the  small  sciatic  also  supplies 
sensation  to  the  perineum,  and  thus  in  perineal  abscess  pain 
is  frequently  referred  to  the  gluteal  region  and  posterior  part 
of  the  thigh. 

In  the  female  the  urogenital  triangle  is  perforated  by 
the  vaginal  orifice,  the  vulva  forming  practically  a  cleft 


THE  PELVIS  289 

between  two  halves  of  a  rudimentary  scrotum.  The  deep 
layer  of  superficial  fascia  runs  through  the  labia  majora  to 
ascend*  on  to  the  abdomen.  Rupture  of  the  perineum  occurs 
frequently  in  connection  with  labour,  and  may  extend  into 
the  rectum.  In  such  cases  the  pelvic  organs  are  deprived  of 
considerable  support,  and  may  project  through  the  vulva, 
forming  a  vesicocele  or  rectocele. 

The  ANAL  TRIANGLE,  occupying  the  posterior  portion  of 
the  perineum,  contains  the  rectum  and  ischio-rectal  fossae. 
The  rectum  and  anus  are  situated  centrally,  being  bounded 
on  either  side  by  the  ischio-rectal  fossae.  Each  ISCHIO-RECTAL 
FOSSA  is  wedge-shaped,  the  base  being  directed  downwards, 
while  the  apex,  2j  inches  from  the  surface,  corresponds  to 
the  position  of  the  white  line,  where  the  anal  and  obturator 
fasciae  join,  and  is  directed  upwards  and  backwards.  The 
triangle  is  bounded  by  the  levator  ani,  covered  on  its  inferior 
surface  by  the  anal  fascia,  and  the  external  sphincter  internally, 
while  it  is  bounded  externally  by  the  obturator  externus  muscle, 
covered  on  its  inner  surface  by  the  obturator  fascia.  An- 
teriorly the  fossa  is  limited  by  the  transversus  perinei  muscle 
and  base  of  the  triangular  ligament,  and  posteriorly  by  the 
margin  of  the  gluteus  maximus  muscle ;  but  two  small  exten- 
sions occur  :  an  anterior  (pubic  recess) ,  extending  beneath  the 
transversus  perinei  between  the  obturator  internus  and 
levator  ani ;  and  a  posterior  between  the  gluteus  maximus 
and  great  sacro-sciatic  ligament  and  the  coccyx  to  the  level 
of  the  ischial  spine  and  coccygeus  muscle.  The  fossa  is 
occupied  by  a  quantity  of  fatty  connective  tissue  continuous 
with  the  surrounding  subcutaneous  fatty  tissue,  and  the  two 
fossae  communicate  freely  behind  the  anus  with  one  another. 
This  tissue  by  yielding  permits  of  faecal  dilatation  of  the 
rectum,  while  in  labour  the  fossae  become  almost  obliterated 
by  distension  of  the  vagina.  As  the  edge  of  the  gluteus 
maximus  overlaps  this  pad,  it  may  indirectly  assist  the 
levator  ani.  The  inferior  hcemorrhoidal  vessels  and  nerves 
pierce  the  obturator  fascia  near  the  posterior  part  of  the  space, 
and  pass  downwards  and  inwards  toward  the  rectum.  The 
perineal  branch  of  the  fourth  sacral  becomes  superficial  near 
the  tip  of  the  coccyx,  and  small  branches  of  the  small  sciatic 
nerve  and  sciatic  artery  curve  round  the  lower  border  of  the 
gluteus  maximus,  while  the  superficial  perineal  vessels  and 

19 


290  SURGICAL  ANATOMY 

nerves  enter  the  anterior  portion  of  the  space,  and  imme- 
diately leave  it  again  by  piercing  the  triangular  ligament. 

ALCOCK'S  CANAL,  situated  in  the  outer  wall  of  the  ischio- 
rectal  fossa,  is  formed  by  a  splitting  of  the  obturator  fascia, 
and  contains  from  above  downwards  the  dorsal  nerve  of  the 
penis,  third  part  of  internal  pudic  artery  with  venae  comites, 
and  perineal  division  of  pudic  nerve. 

The  RECTUM  commences  opposite  the  body  of  the  third 
sacral  vertebra,  and,  descending  in  front  of  the  sacrum  and 
coccyx,  runs  forwards  for  ij  inches  upon  the  pelvic  floor, 
formed  by  the  two  levatores  ani,  and  then,  bending  downwards 
and  backwards,  it  pierces  the  pelvic  floor  to  terminate  at  the 
anus.  About  6  inches  in  length,  it  has  no  mesentery  and 
only  a  partial  peritoneal  covering,  while  instead  of  presenting 
three  muscular  bands  and  general  sacculation  as  the  colon 
does,  it  presents  two  wide  longitudinal  muscular  bands,  the 
one  anterior,  the  other  posterior,  slight  sacculation  occurring 
laterally  between  these  bands.  In  addition  to  the  course 
described  above,  the  rectum  presents  lateral  curves,  which 
are  maintained  by  the  muscular  bands.  These  curves  are 
generally  three  in  number,  an  upper  and  lower  with  the  con- 
cavity to  the  left,  while  the  intermediate  one,  which  is  like- 
wise the  most  prominent,  has  the  concavity  to  the  right. 
The  concavities  are  marked  by  furrows  externally,  and  by 
marked  crescentic  projections — the  rectal  valves,  or  valves 
of  Houston — internally.  As  those  valves  occasionally  ob- 
struct the  passage  of  long  instruments,  it  is  well  to  remember 
that  the  main  one  projecting  from  the  right  side  is  situated 
about  3  inches  above  the  anus,  while  the  other  two,  less  marked 
and  projecting  from  the  left  side,  are  situated  respectively 
ij  inches  above  and  below  the  middle  one.  The  curving 
increases  the  length  of  the  rectum,  and  also  delays  the  passage 
of  and  supports  the  bowel  contents,  and  the  rectal  valves 
also  play  an  important  part  in  so  doing.  These  valves 
become  most  prominent  when  the  bowel  is  distended,  and  are 
excellently  seen  when,  the  patient  lying  inverted,  a  speculum 
is  introduced  through  the  anus,  and  the  rectum  distends  with 
air.  When  distended  the  rectum  occupies  the  greater  portion 
of  the  posterior  division  of  the  pelvis,  obliterating  the  lateral 
or  pararectal  fossae.  About  i  inch  in  diameter  at  its  upper 
extremity,  it  dilates  in  its  lower  two-thirds  to  form  the  rectal 


THE  PELVIS  291 

ampulla.  At  the  point  of  the  last  sharp  curve  backwards, 
the  anterior  rectal  wall  sometimes  projects  forwards  and 
even  downwards,  forming  a  small  anterior  pouch.  This  is 
most  apt  to  occur  in  multiparae. 

The  relationship  of  the  peritoneum  to  the  rectum  is  of  im- 
portance in  excision  of  the  rectum  and  similar  operations.  At 
its  commencement  the  rectum  is  covered  both  in  front  and 
laterally  by  peritoneum,  then  the  lateral  portions  become 
uncovered,  and,  finally,  at  an  average  distance  of  3  inches  from 
the  anus,  the  peritoneum  is  reflected  from  the  front  of  the 
bowel  on  to  the  posterior  surface  of  the  bladder  and  the  vesiculi 
seminales,  forming  the  recto-vesical  peritoneal  pouch.  Thus 
this  pouch  is  generally  opened  into,  when,  in  excising  the 
rectum,  more  than  the  last  3  inches  are  exposed,  but  the  exact 
position  of  the  pouch  varies  between  i  inch  and  4^  inches 
above  the  anus,  and  is  partly  influenced  probably  by  the 
amount  of  distension  of  bladder  and  rectum.  In  the  female 
the  peritoneum  is  reflected  at  the  same  level  on  to  the  upper 
part  of  the  vagina,  cervix,  and  broad  ligaments,  forming  the 
fundus  of  the  pouch  of  Douglas  (recto-vaginal  pouch).  The 
lateral  reflections  are  higher  up,  about  5  inches  from  the  anus, 
and  form  pararectal  fosses,  when  the  rectum  is  empty.  These 
fossae  are  generally  occupied  by  small  intestine,  but,  when 
the  rectum  is  distended,  it  generally  occupies  and  obliterates 
these  spaces.  Below  the  level  of  the  recto-vesical  pouch,  the 
rectum  is  surrounded  by  the  rectal  fascia',  which  is  derived  from 
the  visceral  layer  of  the  pelvic  fascia.  Here,  also,  but  for 
the  interposition  of  this  fascia,  bladder  and  rectum  are  in 
contact  with  one  another  over  a  triangular  area  about  i  inch 
long,  whose  base  corresponds  to  the  line  of  reflection  of  the 
peritoneum,  and  whose  apex  is  situated  at  the  base  of  the 
prostate,  while  the  lateral  limits  are  formed  by  the  vesiculi 
seminales. 

Through  this  triangular  area  the  bladder  has  been  tapped 
per  rectum,  and  the  examining  finger,  introduced  per  rectum, 
can  sometimes  detect  the  presence  of  a  posterior  prostatic 
pouch  of  the  bladder  in  cases  of  enlarged  prostate,  and  even 
perhaps  a  stone  lying  in  it.  The  vesiculi  seminales  can  also 
be  examined  per  rectum,  and  various  changes,  as,  for  example, 
their  hardness  in  certain  stages  of  tubercular  disease,  noted. 
Sometimes  they  may  be  pressed  on  by  straining  at  stool,  and 

19 — 2 


292  SURGICAL  ANATOMY 

thus  emptied,  causing  a  so-called  '  spermatorrhoea.'  In 
front  of  the  vesiculi  seminales,  close  to  the  bladder  wall,  are 
the  ureters,  which  are  not  easily  felt.  The  vasa  deferentia, 
however,  lying  first  on  the  inner  borders  of  the  vesiculi 
seminales,  and  then  lying  together  for  a  short  distance  above 
the  base  of  the  prostate,  may  be  made  out.  Nearer  the  anus, 
and  also  in  front,  the  prostate  gland  can  be  felt,  and,  when 
enlarged,  it  projects  markedly  into  the  rectum,  giving  the 
patient  the  feeling  that  he  cannot  empty  the  bowel,  and 
sometimes  even  leading  to  partial  obstruction.  It,  too, 
when  enlarged,  may  be  pressed  on  during  defaecation,  causing 
pain  if  inflamed,  and  sometimes  also  producing  a  so-called 
'  spermatorrhoea  '  from  the  discharge  of  its  secretion  by  the 
penis.  In  the  female  this  portion  of  the  rectum  is  in  relation 
to  the  vagina,  and  advantage  may  be  taken  of  this  in  rectal 
examination  to  evaginate  the  lower  rectal  wall  through  the 
anus  by  the  finger  introduced  into  the  vagina.  At  the  upper 
part,  the  os  and  cervix  uteri  may  be  felt,  sometimes  projecting 
markedly  into  the  rectum,  and  suggesting  the  presence  of 
tumour.  Laterally  also,  particularly  in  the  child,  the  lateral 
pelvic  wall  over  the  acetabulum  may  be  explored,  and  disease 
of  the  acetabulum,  with  extension  of  tubercular  pus  to  the  inner 
side  of  the  pelvis,  detected.  Through  the  posterior  rectal 
wall  the  coccyx  may  be  felt,  and  possibly  part  of  the 
sacrum,  and  this  wall  is  also  in  relation  to  the  coccygei 
and  levatores  ani  muscles,  sacro  -  sciatic  ligaments  and 
haemorrhoidal  vessels  and  lymphatics.  Laterally,  below  the 
peritoneal  reflection,  the  rectum  is  in  'relation  to  the  vasa 
deferentia  and  upper  extremity  of  the  vesiculi  seminales, 
and  receives  the  middle  hsemorrhoidal  vessels,  enclosed 
in  a  layer  of  connective  tissue,  derived  from  the  pelvic 
wall,  and  called  the  lateral  ligament  of  the  rectum.  The 
rectum  may  also  be  examined  for  tumours  such  as  polypi, 
which  are  frequently  situated  not  very  far  from  the  anal 
orifice,  or  for  carcinoma,  which  is  frequently  only  to  be  felt 
by  a  long  finger.  An  excellent  view  of  the  interior  of  the 
rectum  may  be  obtained  by  inverting  the  patient  and  stretch- 
ing the  sphincter,  the  rectum  then  distending  with  air. 

The  last  inch  or  so  of  the  rectum  directed  downwards  and 
backwards  is  sometimes  spoken  of  as  the  anal  canal.  It  is 
surrounded  by  the  internal  and  external  sphincters,  which, 


THE  PELVIS  293 

assisted  by  the  levatores  ani,  compress  it  laterally,  thus  pre- 
senting an  antero-posterior  slit.  It  is  related  in  front  to  the 
mass  *  of  tissue  known  as  the  perineal  body,  where  several 
perineal  muscles  meet ;  behind  to  the  tissue  between  the 
rectum  and  the  coccyx,  called  the  ano-coccygeal  body ;  while 
laterally  it  is  in  relation  to  the  fat  of  the  ischio-rectal 
fossa. 

The  mucous  membrane  of  this  part,  becoming  continuous 
with  the  anal  skin  at  '  Hilton's  white  line,'  presents  a  series 
of  slight  vertical  ridges — columns  of  Morgagni — which 
become  continuous  above  with  the  mucous  membrane  of  the 
rectum  proper  at  the  ano-rectal  line.  At  the  anal  extremity 
of  each  of  the  intervening  depressions  is  a  small  anal  valve, 
opening  into  a  small  rectal  sinus  in  the  submucous  tissue. 
These  small  valves  are  sometimes  torn  by  scybalous  masses, 
and  are  said  to  give  rise  to  fissure  of  the  anus.  The  ex- 
amining finger  notes  the  smooth  character  of  this  portion  of 
the  mucous  membrane  and  the  underlying  firm  smooth  sur- 
faces of  the  resisting  sphincters.  Where  a  stricture  exists,  this 
is  frequently  detected  only  a  short  distance  in,  presenting 
a  hard,  possibly  sharp,  resisting  ring. 

The  anus  is  capable  of  very  considerable  distension  ii 
done  gradually,  and  a  small  hand  has  even  been  introduced 
for  examination  of  various  organs.  As,  however,  the  hand 
rapidly  cramps  from  pressure,  it  is  of  little  service.  The 
rectum  is  supplied  by  the  middle  sacral  and  superior,  middle, 
and  inferior  hsemorrhoidal  arteries,  of  which  the  first  two  are 
single,  and  the  others  dual  vessels.  The  middle  sacral  arises 
from  the  aorta,  and  its  supply  is  insignificant.  The  superior 
hczmorrhoidal ,  the  principal  blood-supply,  is  the  continuation 
of  the  inferior  mesenteric.  It  supplies  numerous  branches 
to  the  rectum,  which  may  be  traced  almost  to  the  anus, 
piercing  the  muscular  coat  3  inches  above  the  anus,  beyond 
which  point  it  supplies  chiefly  mucous  membrane.  The 
middle  hcemonhoidal  arises  from  the  internal  iliac,  reaches 
the  rectum  about  3  inches  above  the  anus,  and  anastomoses 
with  both  the  superior  and  inferior  haemorrhoidal  vessels. 
The  inferior  hcemorrhoidal  rises  from  the  internal  pudic  of 
the  internal  iliac,  and  supplies  chiefly  the  anal  portion.  The 
veins  of  the  rectum  are  arranged  in  two  main  plexuses — the 
internal  hcemorrhoidal,  situated  in  the  submucous  coat  ;  and 


294  SURGICAL  ANATOMY 

the  external  htemorrhoidal,  situated  in  the  external  coat.  The 
veins  constituting  the  internal  haemorrhoidal  plexus  commence 
in  a  number  of  small  anal  veins,  radially  placed  round  the 
anus,  and  situated  in  the  submucous  tissue.  They  join  to 
form  larger  and  tortuous  vessels,  which,  ascending  in  the 
columns  of  Morgagni,  anastomose  to  form  the  plexus,  and 
frequently  present  small  dilatations,  which  may  represent 
starting-points  for  haemorrhoids.  Ultimately  they, .  pierce 
the  muscular  coat  about  the  middle  of  the  rectum,  and  join 
the  superior  haemorrhoidal  vein. 

Hemorrhoids  consist  of  a  varicosity  of  the  veins  of  the 
internal  haemorrhoidal  plexus,  and  are  classified  as  internal 
when  they  affect  those  in  the  region  of  the  columns  of 
Morgagni  and  are  covered  by  mucous  membrane,  and  as 
external  when  situated  beneath  the  skin  at  the  anal  orifice. 
Internal  haemorrhoids  are  not  infrequently  associated  with 
prolapse  of  the  mucous  membrane,  so  that  they  may 
even  appear  externally,  and  are  sometimes  constricted 
by  the  sphincter,  cure  taking  place  by  sloughing.  Several 
anatomical  causes  may  be  found  for  haemorrhoids  :  ^ (a)  up- 
right posture,  with  veins  running  vertically  in  a  lax  mucous 
membrane  (scybalous  masses  may  press  on  these  vertical 
veins)  ;  (b)  the  superior  haemorrhoidal,  a  long  vein  without 
valves,  communicates  with  the  portal  system,  and  is  liable 
to  congestion  ;  it  is  also  liable  to  be  pressed  on  by  loaded 
rectum.  The  various  veins  which  pass  out  through  the  rectal 
wall  unite  to  form  the  external  haemorrhoidal  plexus,  and  from 
this  plexus  the  superior  haemorrhoidals  go  to  join  the  inferior 
mesenteric,  which  joins  the  portal  vein  ;  the  middle  haemor- 
rhoidal joins  the  internal  iliac,  and  the  inferior  haemorrhoidal 
joins  the  internal  pudic  of  the  internal  iliac.  Thus  portal 
and  systemic  systems  communicate  on  the  rectum. 

The  lymphatics  pass  chiefly  to  some  rectal  glands  lying  in 
the  outer  coat  of  the  bowel  in  the  course  of  the  superior 
haemorrhoidal  vein,  and  thence  to  the  sacral  glands  in  front 
of  the  sacrum.  Some  of  these  from  the  anal  region  join  the 
cutaneous  lymphatics,  and  so  reach  the  superficial  inguinal 
glands,  and  a  few  are  said  to  pass  to  the  internal  iliac  glands 
lying  on  the  lateral  pelvic  wall.  The  rectum  is  supplied  by 
the  second,  third,  and  fourth  sacral  nerves,  together  with 
sympathetic  fibres  from  the  mesenteric  and  hypogastric 


THE  PELVIS  29$ 

plexuses.     The  anal  canal  and  external  sphincter  are  supplied 
by  the  inferior  haemorrhoidal  branch  of  the  internal  pudic. 

The*  sacral  nerves  convey  motor  impulses  to  the  longitudinal 
muscle  fibres  and  inhibiting  impulses  to  the  circular,  while 
the  sympathetic  does  the  reverse.  While  the  anal  portion 
of  the  bowel  is  very  sensitive,  the  portion  above  is  very 
insensitive,  so  that  considerable  damage  may  be  done  without 
a  patient  being  aware  of  the  fact.  In  rectal  affections  pain 
is  sometimes  referred  to  the  perineum,  penis,  and  even  down 
the  thigh,  owing  to  the  pudic  and  small  sciatic  nerves  arising 
from  the  same  section  of  the  cord.  The  fourth  sacral  nerve 
supplies  both  rectum  and  neck  of  bladder,  and  thus  retention 
of  urine  frequently  follows  operations  on  the  rectum,  par- 
ticularly, it  is  said,  when  the  sphincter  is  stretched  antero- 
posteriorly  instead  of  laterally.  The  reflex  defecation  centre 
is  in  the  lumbar  region,  and  may  act  even  when  separated 
from  the  brain.  Destruction  of  the  centre  causes  incon- 
tinence of  faeces.  Where  the  pelvic  colon,  or  upper  rectum, 
.  is  greatly  distended  with  faecal  matter,  or  is  affected  with 
carcinoma,  the  obturator  nerve  is  sometimes  pressed  on,  causing 
the  patient  to  complain  of  pain  in  the  knee. 

In  the  child  the  rectum  is  relatively  larger  in  its  upper  part, 
is  nearly  straight,  almost  veitical,  and  is  partly  abdominal 
rather  than  pelvic.  At  birth,  also,  the  peritoneal  covering 
descends  to  the  base  of  the  prostate,  and,  as  the  other  con- 
nections are  loose,  prolapse  is  frequently  met  with.  The  pro- 
lapse in  such  cases  is  generally  partial,  consisting  only  of 
mucous  membrane.  Complete  prolapse  of  the  whole  bowel 
wall  is  not  very  common,  and  is  generally  associated  with 
weakness  of  the  pelvic  floor,  and  severe  and  repeated  straining 
from  some  cause  such  as  urethral  stricture.  In  such  cases 
it  is  well  to  remember  that  the  herniated  portion  consists  of 
a  double  layer  of  bowel,  and  that  a  peritoneal  pouch  fre- 
quently exists  between  the  layers  in  front,  into  which  a  portion 
of  small  intestine  may  descend,  causing  a  sudden  increase  in 
the  size  of  the  swelling. 

In  the  foetus  the  urinary  and  rectal  systems  terminate 
together  in  the  earlier  stages  in  a  common  space,  or  cloaca. 
Normally  the  anterior  or  urogenital  section  becomes  separated 
from  the  posterior  or  rectal  portion.  The  posterior  extremity 
of  the  bowel  does  not  open  on  the  surface  of  the  body,  but  a 


296  SURGICAL  ANATOMY 

depression  from   the  surface,   called  the  proctodceum,  grows 
down  to  meet  it,  and  forms  the  anal  portion  of  the  bowel. 
At  first  the  protodaeum  is  blind,  as  is  likewise  the  lower  end 
of  the  bowel,  but  finally  by  absorption  of  the  anal  membrane 
the  lumen  of  the  canal  is  completed.     Various  deformities 
are  seen  affecting  the  lower  end  of  the  rectum.     The  canal 
may  be  patent  but  narrowed,  forming  a  congenital  stricture. 
The  most   common   condition  is   that   of  imperforate   anus, 
where,  owing  to  persistence  of  the  cloacal  membrane,  a  septum 
exists  at  the  ano-rectal  junction.     If  the  proctodaeum  forms, 
but  the  rectum  ends  unduly  high  up,  the  condition  is  known 
as  absent  rectum,  while  the  anus  may  or  may  not  be  present. 
The  rectum  may  open  into  the  bladder,  or  a  cloaca  may  persist. 
Where  only  a  septum  exists,  it  may  be  perforated  by  the 
cautery.     Where,   on  the  other  hand,  the  lower  rectum   is 
absent,  an  inguinal  colotomy  is  necessary  (Littre's  operation). 
Two  forms  of  rectal  stricture  have  already  been  mentioned, 
the  one  congenital,  and  the  other  fibrous,  and  generally  due 
to    syphilis.     CARCINOMA,    however,    constitutes    the    most, 
important  form  of  rectal  stricture,  and,  indeed,  the  rectum 
is  the  most  frequent  site  of  bowel  carcinoma.     When  situated 
close  to  the  anus,  it  may  be  removed  by  making  a  circular 
incision  round  the  anus,  and  then  separating  a  sleeve  of  bowel, 
and  pulling  it  down  from  above.     As  a  rule,  however,  the 
tumour  is  situated  some  3  or  4  inches  above  the  anus,  in  a 
position  where  its  lower  extremity  may  just  be  touched  by 
the   examining  finger.     In  such   cases,   after   a  preliminary 
colotomy,  the  affected  portion  of  bowel  is  removed  by  Kraske's 
operation,   or  one  of  its  modifications,   in  which   a  median 
incision  is  made  over  the  lower  portion  of   the  sacrum  and 
coccyx,  and  extending  to  about  i  inch  from  the  anus.     The 
tissues  on  the  left  side,  including  the  origin  of  the  gluteus 
maximus,  are  reflected,  as  are  likewise  the  attachments  of  the 
left  sacro-sciatic  ligaments,  coccygeus  and  levator  ani  muscles, 
to  the  sacrum  and  coccyx.     The  anterior  surface  of  the  sacrum 
is  next  cleared  by  the  periosteal  elevator,  the  median    and 
lateral   sacral    arteries    and    plexus    of    veins   being   shelled 
forward,  and  then  the  last  two  pieces  of  the  sacrum,  or  at  least 
their  left  halves,  and  the  whole  coccyx,  are  removed,  and  the 
bowel   exposed  with   the  hsemorrhoidal   vessels.      It   is   not 
advisable  to  cut  away  more  than  the  last  two  pieces  of  the 


THE  PELVIS  297 

sacrum,  as  then  the  third  sacral  nerve  would  be  injured 
(Bardenheuer).  The  sphincters  are  supplied  by  the  third 
and  fourth  sacral  nerves,  and  the  levator  ani  by  the  third 
chiefly,  while  the  bladder  is  supplied  by  the  second,  third, 
and  fourth.  Thus,  if  the  third  and  fourth  nerves  were  destroyed, 
the  sphincter  would  be  paralyzed,  and  the  control  of  the 
bladder  lost,  producing  incontinence.  If  it  is  necessary  to 
bring  down  more  bowel  from  above,  this  may  be  done  by 
opening  into  the  peritoneum,  which  so  far  has  been  intact, 
and  pulling  down.  The  diseased  portion  is  removed,  cutting 
wide  of  the  disease  both  above  and  below,  and  the  healthy 
ends  united.  In  this  operation  the  anus  with  the  sphincters 
is  preserved  intact.  The  glands  lying  in  front  of  the  sacrum, 
and  in  the  iliac  regions,  may  be  removed  if  affected,  and  the 
portion  of  sacrum  removed  may  be  replaced  after  the  opera- 
tion. Where  the  upper  portion  of  the  rectum  is  affected,  it 
may  be  reached  by  a  combination  of  peritoneal  and  sacral 
routes. 

Fissure  and  fistula  frequently  affect  the  anus.  Fissure 
is  a  narrow  crack  in  the  anal  skin,  extending,  perhaps,  as  far 
as  one  of  the  anal  valves,  between  the  columns  of  Morgagni. 
It  is  extremely  painful  owing  to  the  exposure  of  one  or  more 
nerve  terminations,  and  the  constant  movements  of  the  rectum 
with  respiration,  and  of  the  sphincter.  In  the  more  severe 
cases  the  sphincter  may  be  overstretched  so  as  temporarily 
to  paralyze  it,  and  the  ulcer  excised. 

Fistula  in  ano  may  be  produced  in  much  the  same  manner 
as  the  fissure,  the  mucous  membrane  about  the  same  site 
(J  inch  above  the  anus)  being  damaged  by  scybalous  masses, 
etc.  Organisms  thus  gain  access  to  the  lax  submucous  layer, 
and  in  it  they  proliferate,  and  give  rise  to  pus  which  passes 
down  in  this  layer  and,  therefore,  on  the  bowel  side  of  the 
sphincter,  until  it  reaches  the  subcutaneous  tissues,  which, 
being  more  resistant,  limit  the  progress  of  the  pus,  which  at 
this  point  forms  an  abscess.  This  abscess  may  immediately 
point  on  the  surface,  and  burst,  producing  the  fistula,  or, 
as  not  infrequently  happens,  it  first  bursts  into  the  ischio- 
rectal  fossa,  which  is  filled  with  pus  prior  to  the  external 
bursting,  forming  an  ischio  -  rectal  abscess.  Owing  to  the 
length  and  tortuosity  of  the  track,  the  condition  does  not 
heal,  but  a  persistent  discharge  is  kept  up,  and  frequently 


298  SURGICAL  ANATOMY 

a  small  mass  of  granulation  tissue,  called  a  '  sentinel  pile/ 
forms  at  the  external  orifice.  Treatment  consists  in  over- 
stretching the  sphincter,  and  then  carefully  passing  a  director 
along  this  superficial  and  tortuous  channel,  until  the  inner 
opening  is  reached,  and  slitting  it  open,  removing  diseased 
track,  and  packing  so  as  to  produce  healing  by  granulations 
from  the  bottom.  Care  must  be  taken  in  introducing  the 
director  not  to  introduce  it  into  the  ischio-rectal  fossa,  or  to 
force  it  along  an  imaginary  fistula.  If  such  be  done,  the 
fistula  will  not  be  laid  open,  and  the  sphincter  may  be  cut. 

The  lower  colon  and  the  rectum  possess  very  considerable 
absorptive  power,  which  is  utilized  in  feeding  by  rectal 
injections  of  predigested  foods.  In  cases  of  shock  from  loss 
of  blood  many  ounces  of  saline  solution  will  generally  be 
rapidly  absorbed,  and  it  should  be  remembered  when  admin- 
istering alkaloids  by  rectum  that  their  action  so  given  is 
only  less  powerful  than  when  given  hypodermically. 


SECTION  IV 
LOWER   EXTREMITY 

THE  HIP. — This  region  may  be  subdivided  into  gluteal  and 
adductor  portions,  and  region  of  Scarpa's  triangle. 

Gluteal  Region — SURFACE  ANATOMY. — The  gluteal  region 
is  bounded  above  by  the  iliac  crest,  and  below  by  the  gluteal 
fold  ;  internally  by  the  intergluteal  sulcus,  and  externally  by 
a  line  from  the  anterior  superior  spine  to  the  tip  of  the  great 
trochanter.  The  anterior  superior  spine  is  generally  visible 
as  a  landmark,  and  can  be  easily  palpated.  The  crest  of  the 
ilium  may  be  obvious,  or  may  be  overhung  by  flesh,  and 
terminates  posteriorly  in  the  posterior  superior  spine,  which 
is  frequently  marked  by  a  dimple,  and  is  on  a  level  with  the 
second  sacral  spine,  and  just  behind  the  centre  of  the  sacro- 
iliac  articulation.  The  gluteal  fold  does  not  correspond  to 
the  lower  border  of  the  gluteus  maximus  muscle,  but  lies  con- 
siderably above  it.  It  extends  horizontally  outwards,  and  is 
most  distinct  when  the  thigh  is  extended,  becoming  obliterated 
when  it  is  flexed  to  a  right  angle.  Thus,  in  hip  disease,  where 
the  limb  is  flexed,  loss  of  the  gluteal  fold  is  an  early  sign,  and, 
later,  this  symptom  becomes  more  marked  from  atrophy  of  the 
muscles. 

The  GREAT  TROCHANTER  is  an  obvious  landmark,  although 
in  a  fat  person  its  position  may  be  indicated  by  a  depression. 
It  is  covered  by  the  fascial  insertion  of  the  gluteus  maximus, 
and  the  tendon  of  the  gluteus  medius  passes  over  its  upper 
border.  It  becomes  very  prominent  when  the  gluteal  muscles 
atrophy,  and  on  abduction  of  the  thigh  these  muscles  are 
relaxed,  and  thus  the  tip  of  the  trochanter  is  more  readily 
palpated.  Normally  it  should  occupy  a  position  midway 
between  the  anterior  superior  spine  and  the  tuber  ischii,  and 

299 


300  SURGICAL  ANATOMY 

should  just  touch  a  line  drawn  between  these  two  points 
(NELATON'S  LINE)  when  the  thigh  is  very  slightly  flexed.  As  it 
is  frequently  of  importance  in  suspected  hip  affections  to  test 
whether  the  head  of  the  femur  is  in  its  position  by  carefully 
noting  that  of  the  great  trochanter,  another  method  has  been 
devised  by  Bryant  (BRYANT'S  TRIANGLE).  With  the  patient 
lying  on  his  back,  a  vertical  line  is  dropped  from  the  anterior 
superior  spine,  and  a  second  line  drawn  from  the  same  point 
to  the  tip  of  the  great  trochanter.  A  third  line,  at  right  angles 
to  the  vertical  line,  is  now  dropped  from  the  trochanteric  tip, 
and  this  third  line,  which  completes  the  triangle,  is  compared 
in  length  with  its  neighbour  of  the  other  side.  A  line  drawn 
from  the  posterior  superior  spine  to  the  tip  of  the  trochanter 
indicates  the  interspace  between  the  gluteus  medius  and  the 
pyriformis,  and  the  point  of  emergence  of  the  gluteal  artery 
from  the  pelvis  is  at  the  junction  of  its  inner  and  middle  one- 
third.  A  line  drawn  from  the  posterior  superior  spine  to  a 
point  midway  between  the  tuber  ischii  and  great  trochanter 
crosses  the  gluteal  artery  at  the  junction  of  its  upper  and 
middle  one-third,  while  the  junction  of  its  middle  and  lower 
one-third  indicates  the  point  of  emergence  of  the  great  sciatic 
nerve  from  the  sacro-sciatic  foramen.  A  line  drawn  from  the 
posterior  superior  spine  to  the  outer  part  of  the  tuber  ischii 
crosses  the  posterior  inferior  spine  2  inches  down,  and  the 
ischial  spine  4  inches  down.  The  pudic  artery  crosses  over  the 
ischial  spine  in  passing  from  the  great  to  the  small  sacro- 
sciatic  foramen,  and  the  sciatic  artery  reaches  the  gluteal 
region  at  the  junction  of  the  middle  and  lower  one-third  of 
this  line. 

The  TROCHANTERIC  FOSSA  is  the  depression  behind  the  tro- 
chanter into  which  the  fingers  can  be  pushed  deeply  normally, 
but  which  is  frequently  obliterated  in  extracapsular  fracture 
of  the  neck.  The  tuber  ischii  is  covered  by  the  gluteus  maxi- 
mus  when  the  limb  is  extended,  but  is  exposed  when  the  limb 
is  flexed  to  a  right  angle,  and  is  then  easily  palpable. 

The  SKIN  over  the  gluteal  region  is  thick,  and  contains 
numerous  sebaceous  glands,  and  is  a  frequent  seat  of  boils. 
The  SUBCUTANEOUS  TISSUE  is  very  fat,  and  is  directly  con- 
tinuous with  the  fatty  tissue  which  occupies  the  ischio-rectal 
fossa,  and  with  a  layer  lying  under  the  gluteus  maxim  us. 


LOWER  EXTREMITY  301 

This  layer  under  the  gluteus  maximus  communicates  through 
the  sacro-sciatic  foramina  with  the  intrapelvic  connective 
tissue,  a£id  that  of  the  ischio-rectal  fossa  and  that  descending 
the  back  of  the  thigh  along  the  sciatic  nerve.  The  laxity  of 
this  tissue  favours  the  formation  of  large  collections  of  pus 
or  blood,  and  lipomata  are  frequently  found  in  this  region. 
The  FASCIA  LATA  in  this  region  is  strong  and  tense.  Attached 
above  to  the  outer  lip  of  the  iliac  crest  and  to  the  sacrum 
and  coccyx  behind,  it  splits  in  front  to  enclose  the  tensor 
fasciae  femoris  ;  and,  again,  lying  on  the  gluteus  medius, 
splits  to  enclose  the  gluteus  maximus.  Effusions  of  blood, 
or  abscesses,  occurring  beneath  this  layer,  are  much  circum- 
scribed, and  frequently  give  rise  to  much  pain.  They  may 
travel  down  the  thigh,  or  even  farther,  before  reaching  the 
surface,  or  may  enter  the  pelvis  through  the  sciatic  foramina  ; 
while,  conversely,  a  pelvic  abscess  may  find  its  way  below 
the  gluteus  maximus,  as  may  also  pus  from  the  hip-joint  by 
perforation  of  the  posterior  aspect  of  the  capsule.  A  thickened 
band  of  the  fascia — the  ilio-tibial  band — into  which  the  tensor 
fasciae  femoris  is  inserted,  runs  from  the  iliac  crest  to  the  outer 
tuberosity  of  the  tibia  and  head  of  the  fibula.  A  tense  portion 
of  this  band  runs  between  the  iliac  crest  and  the  great  tro- 
chanter,  which  becomes  relaxed  in  fractures  of  the  neck  of  the 
femur. 

The  GLUTEUS  MAXIMUS  is  the  most  massive  layer  of  muscle 
in  the  body,  and  is  inserted  below  into  the  fascia  lata  over- 
lying the  great  trochanter,  and  into  the  back  of  the  femur. 
Its  lower  margin  is  oblique,  and  lies  well  below  the  gluteal  fold. 
It  has  been  ruptured  by  muscular  violence.  The  gluteus 
maximus  is  separated  from  the  outer  surface  of  the  great 
trochanter,  the  tuber  ischii,  and  the  outer  tendinous  surface  of 
the  vastus  externus  by  BURS.E.  The  bursa  over  the  great 
trochanter  is  occasionally  affected  by  chronic  inflammatory 
processes,  causing  the  limb  to  be  kept  flexed  and  adducted, 
and  when  it  bursts  it  generally  gives  rise  to  a  sinus  difficult  to 
heal  on  account  of  the  constant  movement  of  the  gluteus 
maximus,  while,  on  the  other  hand,  the  disease  may  spread  to 
the  bone. 

The  GLUTEI  medius  and  minimus  are  also  provided  with 
bursae  over  the  great  trochanter,  into  which,  along  with  the 
PYRIFORMIS,  OBTURATOR  internus  and  GEMELLI,  they  are  in- 


302  SURGICAL  ANATOMY 

serted.  The  bursa  over  the  ischial  tuberosity  is  frequently 
enlarged,  giving  rise  to  the  condition  known  as  Weaver's  or 
Lighterman's  bottom.  It  may  cause  pressure  on  the  perineal 
branch  of  the  small  sciatic  nerve,  giving  rise  to  unilateral 
neuralgia  of  the  penis  and  scrotum.  'Pressure  on  the  same 
nerve  as  it  crosses  in  front  of  the  tuber  ischii  from  the  use 
of  a  hard  seat  may  give  rise  to  similar  neuralgia,  temporary 
numbness,  or  anaesthesia.  Small  branches  of  the  gluteal  and 
sciatic  arteries  and  nerves  pierce  the  gluteus  maximus,  while 
under  it  lie  two  groups  of  vessels  and  nerves — those  which 
emerge  above  and  below  the  pyriformis  muscle.  Those  which 
emerge  above  are  the  gluteal  vessels  (posterior  division  of  the 
internal  iliac)  and  superior  gluteal  nerve  from  the  sacral  plexus, 
which  latter  supplies  the  gluteus  medius  and  minimus,  and 
tensor  fasciae  femoris.  The  artery  anastomoses  with  the  deep 
circumflex  iliac  of  the  external  iliac,  the  external  circumflex 
of  the  profunda  femoris,  and  the  sciatic  artery.  It  is  generally 
about  the  size  of  the  ulnar,  but  may  be  larger,  and  has  caused 
death  from  haemorrhage  when  wounded.  As  a  rule,  however, 
the  trunk  escapes,  as  it  is  situated  chiefly  within  the  pelvis. 
The  trunk  is  occasionally  the  seat  of  aneurism,  which,  pressing 
on  the  lumbo-sacral  cord,  gives  rise  to  nerve  symptoms. 
Below  the  pyriformis  are  the  sciatic  vessels  and  nerves,  and  the 
nerve  to  the  quadratus  femoris.  In  addition,  the  internal 
pudic  vessels  and  nerve,  and  nerve  to  the  obturator  internus, 
emerge  from  the  great  sciatic  foramen,  turn  round  the 
ischial  spine,  and  re-enter  the  pelvis  through  the  lesser 
sciatic  foramen.  The  sciatic  artery  from  the  anterior  division 
of  the  internal  iliac  supplies  the  surrounding  muscles, 
anastomoses  with  the  other  vessels,  and  supplies  a  branch 
to  the  great  sciatic  nerve.  The  sciatic,  internal  and  external 
circumflex,  and  the  first  perforating  vessels  form  the  crucial 
anastomosis  about  the  level  of  the  quadratus  lumborum. 
Very  rarely  the  femoral  artery  extends  down  the  back  of  the 
thigh  instead  of  the  front. 

The  GREAT  SCIATIC  NERVE,  the  largest  in  the  body,  is  a  con- 
tinuation of  the  sacral  plexus  (fourth  lumbar  to  third  sacral), 
and  lies  midway  between  the  tuber  ischii  and  the  great  tro- 
chanter.  It  is  a  frequent  seat  of  neuralgia,  called  here  sciatica, 
which  may  be  due  to  pressure  in  the  pelvis  from  tumours, 
engorged  pelvic  veins,  aneurism  of  branches  of  the  internal 


LOWER  EXTREMITY 


303 


Gluteus  maximus 
(origin)   ^ 

Gluteal  artery 
Superior  gluteal  nerve 

Pyriformis 

Internal  pudic  artery 
and  pudic  nerve 
Nerve  to  obturator 

internus 

Great  sacro-sciatic 
ligament 

Sciatic  artery 


Great  sciatic  nerve  and 
comes  nervi  ischiad. 

Long  pudendal  nerve 

Hamstring  muscles 
(origin) 


Adductor  magnus 
(ischio-pubic  portion)— 


Part  of  adductor  magnus— 
from  tuber  ischii  to 
adductor  tubercle 


Lower  part  of 
great  sciatic  nerve 

Int.  popliteal  nerve 

Popliteal  vein 

Popliteal  artery 

Femoral  opening 

Tendon  of 
adductor  magnus- 


Gluteus  medius 
(reflected) 

Lower  branch  of  deep 
div.  of  gluteal  artery 


_  Gluteus  maximus 


A^-- Gluteus  rnaxu 
.5^  (insertion) 


..Obturator  internus 
and  gemelli 

__  Quacratus  femoris 


_.Small  sciatic  nerve 
^..Crucial  anastomosis 


_  .First  perforating  artery 
--•Vastus  externus 

__  Second  perforating  artery 

Third  perforating  artery 

Fourth  perforating  artery 

Femoral  head  of  biceps 
External  popliteal  nerve 


•  Tendon  of  insertion  of  biceps 


FIG.  35. — THE  GLUTEAL  REGION  AND  BACK  OF  THE  THIGH. 
DEEP  DISSECTION.     (From  Buchanan's  "  Anatomy.") 


304  SURGICAL  ANATOMY 

iliac,  sciatic  hernia,  faecal  masses  in  the  rectum,  etc.,  while 
below  the  gluteus  maximus  it  is  comparatively  superficial, 
and  may  be  exposed  to  cold  or  injury.  It  may  be  stretched 
by  flexing  the  extended  limb  on  the  abdomen,  or  it  may  be  cut 
down  on,  picked  up  at  the  lower  margin  of  the  gluteus  maximus, 
and  stretched  by  hand,  the  pelvis  being  raised  by  it  from 
the  table.  A  weight  of  183  pounds  is  said  to  break  the  nerve. 

The  gluteal  region  is  richly  supplied  with  NERVES,  and  has 
well-developed  tactile  sensation.  The  nerve-supply  is  derived 
from  the  twelfth  dorsal,  first  lumbar,  second  and  third  sacral 
segments  (the  latter  segments  also  supplying  the  sexual  organs)  ; 
through  the  lateral  cutaneous  of  the  twelfth  dorsal,  twigs  from 
the  posterior  branches  of  the  lumbar  and  external  cutaneous 
nerves,  iliac  branch  of  the  ilio-hypogastric,  and  branches  of 
the  sacral  nerves  and  of  the  small  sciatic.  The  following 
muscles  lie  under  the  gluteus  maximus  :  the  gluteus  medius, 
pyriformis,  the  obturator  internus,  with  the  gemelli  on  either 
side  ;  quadratus  femoris  ;  hamstrings  arising  from  the  tuber 
ischii  ;  adductor  magnus  ;  and  vastus  externus. 

The  great  sacro-sciatic  ligament  stretches  downwards  from 
the  posterior  inferior  iliac  spine,  sacrum,  and  coccyx  to  the 
tuber  ischii,  while  the  lesser  sciatic  ligament  stretches  down- 
wards and  outwards  from  the  side  of  the  sacrum  to  the  ischial 
spine.  The  latter  converts  the  great  sciatic  notch  into  the 
great  sacro-sciatic  foramen  (which  is  bounded  on  its  inner  side 
by  the  great  ligament),  while  the  great  ligament,  assisted  by 
the  lesser,  converts  the  lesser  notch  into  the  lesser  foramen. 

Wounds  of  the  gluteal  region,  especially  those  entering  behind 
the  great  trochanter,  may  readily  penetrate  the  pelvis  through 
the  sciatic  notch,  and  damage  the  bladder,  ureter,  or  rectum, 
giving  rise  to  fistulae,  while  the  peritoneal  cavity  may  be 
opened  and  peritonitis  result.  The  gluteal  and  sciatic  arteries 
have  been  ligatured  from  the  gluteal  region,  and  might  be 
involved  in  wounds,  while  the  great  sciatic  nerve  might  also 
be  involved. 

A  sciatic  hernia  occasionally  makes  its  way  through  the  great 
sciatic  foramen,  and  appears  above  the  pyriformis  muscle  ; 
rarely  through  the  lesser  foramen,  appearing  below  the 
pyriformis.  Such  herniae  are  more  common  in  women,  are 
generally  small,  and  entirely  under  the  gluteus  maximus. 
When  large,  however,  they  may  appear  under  its  lower  border. 


LOWER  EXTREMITY  305 

The  neck  of  the  sac  is  usually  situated  at  the  fossa  ovarica  in 
the  angle  between  the  internal  iliac  artery  and  its  obturator 
brancrf 

Treatment  should  consist  in  cutting  down  and  out  along  the 
ilio-trochanteric  line  parallel  to  the  fibres  of  the  gluteus 
maximus,  which  are  separated  and  retracted.  The  sac  is 
then  carefully  defined  and  freed  from  adhesions,  remembering 
that  most  of  the  vessels  and  nerves  run  down  and  outwards 
parallel  to  the  fibres  of  the  pyriformis. 

Searpa's  Triangle — SURFACE  ANATOMY. — Scarpa's  triangle 
is  limited  above  by  Poupart's  ligament,  extending  from  the 
anterior  superior  spine  to  the  spine  of  the  pubis  in  a  slight 
curve,  with  the  convexity  downwards.  Owing  to  the  attach- 
ment to  it  of  the  fascia  lata,  it  is  rendered  less  tense  when  the 
thigh  is  flexed,  adducted,  and  rotated  inwards. 

Holden's  line,  extending  outwards  from  the  angle  between 
the  scrotum  and  the  thigh  to  midway  between  the  anterior 
superior  spine  and  tip  of  the  trochanter,  is  said  to  be  visible 
when  the  thigh  is  flexed,  and  to  act  as  a  guide  to  the  capsule  of 
the  hip-joint,  across  the  front  of  which  it  runs.  The  triangle 
is  bounded  externally  by  the  sartorius,  and  internally  by  the 
adductor  longus.  The  sartorius  may  be  rendered  prominent 
by  raising  the  limb  across  the  opposite  knee.  The  tendon  of 
the  adductor  longus  arises  just  below  the  spine  of  the  pubis, 
and  where  this  landmark  cannot  very  easily  be  made  out  in  a 
stout  person,  the  adductor  longus  tendon,  which  may  be 
rendered  tense  by  asking  the  patient  to  adduct  the  limb 
against  some  resistance,  acts  as  a  guide.  The  pulsations  of 
the  femoral  artery  can  generally  be  seen  near  the  base  of  the 
triangle,  and  occasionally  the  vein  bulges  slightly  forwards 
when  the  patient  stands  and  coughs,  thus  resembling  femoral 
hernia.  Other  conditions  resembling  femoral  hernia  are 
femoral  aneurism,  tumours  (particularly  lipomas,  which  are 
sometimes  partially  reducible  through  apertures  in  the  fascia 
lata),  psoas  abscess,  and  enlargement  of  the  glands  in  the 
groin.  The  suppurative  glandular  enlargement,  which  occurs 
in  soft  sore,  etc.,  is  spoken  of  as  a  bubo.  The  lymphatic  glands 
can  frequently  be  felt. 

The  position  of  the  femoral  ring  is  indicated  by  taking  a 
point  i  inch  from  the  pubic  spine  on  a  line  drawn  from  the 
spine  to  the  tip  of  the  great  trochanter,  or  by  taking  a  point 

20 


306  SURGICAL  ANATOMY 

J  inch  inside  the  femoral  artery,  and  close  to  Poupart's  liga- 
ment. The  position  of  the  saphenous  opening  is  sometimes 
marked  by  a  slight  depression  on  the  surface,  or  it  may  be 
indicated  by  taking  a  point  ij  inches  below,  and  external  to, 
the  pubic  spine.  In  thin  persons  the  long  saphenous  vein  can 
frequently  be  made  out  passing  to  the  opening.  A  super- 
numerary mamma  is  occasionally  found  in  the  groin,  and  the 
testicle,  instead  of  descending  into  the  scrotum,  may  descend 
through  the  crural  canal  into  Scarpa's  triangle,  or  even  turn  up 
like  a  femoral  hernia  over  Poupart's  ligament. 

The  SKIN  over  the  triangle  is  thin,  loosely  attached,  and 
distensible,  permitting  large  herniae,  or  tumours,  to  occupy  the 
space.  Incisions  made  parallel  to  Poupart's  ligament  come 
together  easily,  whereas  vertical  ones  tend  to  gape.  Burns  fre- 
quently produce  contraction  deformities,  resulting  in  flexion 
of  the  hip.  The  SUPERFICIAL  FASCIA  contains  a  considerable 
amount  of  fat,  and  near  Poupart's  ligament  is  divisible  into 
two  layers.  Lipomas  frequently  occur  in  this  region,  and 
may  travel,  under  gravity,  some  distance  down  the  thigh. 
Superficial  abscesses  arise  from  infection  of  the  superficial 
lymphatic  glands  from  some  abrasion  of  the  limb,  genitals, 
anus,  or  buttock,  and  generally  do  not  travel  under  this  fascia, 
but  readily  point  through  it  close  under  Poupart's  ligament. 
Branches  of  the  femoral  artery  in  this  region  are  the  superficial 
circumflex  iliac,  epigastric  and  external  pudic,  the  accompany- 
ing veins  discharging  into  the  long  saphenous. 

The  LONG  SAPHENOUS  VEIN  ascends  from  the  dorsum  of 
the  foot,  in  front  of  the  inner  malleolus,  along  the  inside  of 
the  leg  to  the  posterior  aspect  of  the  internal  condyle  of  the 
femur,  where  it  is  in  relation  to  the  long  saphenous  nerve  of 
the  anterior  crural.  Thence  it  runs  upwards  and  outwards 
to  the  saphenous  opening,  pierces  the  cribriform  fascia  and 
anterior  wall  of  the  femoral  sheath,  and  joins  the  femoral 
vein.  In  its  course  it  receives  many  branches,  of  which  the 
chief  are  the  outer  and  inner  superficial  femoral,  which  join 
it  about  the  apex  of  Scarpa's  triangle. 

The  LYMPHATIC  GLANDS  are  arranged  in  superficial  and  deep 
sets.  The  former,  about  twelve  in  number,  are  arranged  in 
two  groups — a  horizontal  close  to  Poupart's  ligament,  and  a 
vertical  along  the  long  saphenous  vein.  The  vertical  group 
receives  the  superficial  lymphatics  of  the  lower  limb,  of  the 


LOWER  EXTREMITY 

i 


307 


24  -- 


Fir,.  36. — THE  FRONT  OF  THE  THIGH  (SCARPA'S  TRIANGLE). 
(From  Buchanan's  "  Anatomy.") 


1.  Crural  branch  of  genito-crural  nerve. 

2.  Superficial  epigastric  artery. 

3.  Common  femoral  artery. 

4.  Hypogastric  branch  of  ilio-hypogastric 

nerve. 

5.  Pectineus. 

6.  Superior  external  pudic  artery. 

7.  Spermatic  cord. 

8.  Inferior  external  pudic  artery. 

9.  Adductor  longus. 

10.  Gracilis. 

11.  Cutaneous  branch  of  obturator  nerve. 

12.  Internal  cutaneous  nerve. 


13-  Vastus  internus. 

14.  Rectus  femoris. 

15.  Sartorius. 

16.  Left  saphenous  vein.  —  i 

17.  Middle  cutaneous  nerve. 

1 8.  Femoral  vein. 

19.  Anterior  crural  nerve. 

20.  Iliacus. 

21.  Tensor  fascia;  femoris. 

22.  Superficial  circumflex  iliac  arterj 

23.  External  cutaneous  nerve. 

24.  Obliquus  cxternus  abdominis. 

2O — 2 


308  SURGICAL  ANATOMY 

perineum,  and  a  few  from  the  inner  surface  of  the  buttock  and 
from  the  external  genitals.  The  horizontal  group  receives 
the  lymphatics  of  the  external  genitals,  the  outer  surface  of 
the  buttock  (to  the  outer  glands) ,  inner  surface  of  the  buttock 
(to  inner  glands),  and  superficial  vessels  of  lower  half  of  the 
abdomen  (to  middle  glands).  The  deep  glands,  some  four  in 
number,  are  situated  along  the  femoral  vein  near  the  crural 
canal,  and  receive  the  deep  lymphatics  of  the  lower  limb, 
and  also  most  of  the  efferent  vessels  from  the  superficial  set. 
The  efferent  vessels  from  the  deep  set  pass  through  the  crural 
canal  to  the  iliac  glands,  three  of  which  lie  immediately  above 
Poupart's  ligament.  One  of  these  glands  is  situated  in  the 
crural  canal,  lying  on  the  septum  crurale.  When  inflamed,  it 
may  cause  much  pain,  and  simulate  strangulated  femoral 
hernia.  Enlargement  of  the  superficial  set  may  stretch 
branches  of  the  anterior  crural  nerve,  and  give  rise  to  much 
pain  and  muscular  spasm. 

The  FASCIA  LATA  forms  a  tubular  investment  for  the 
muscles  of  the  thigh,  being  attached  above  to  the  iliac  crest, 
Poupart's  ligament,  body,  and  ramus  of  the  pubis,  ramus  of 
the  ischium,  great  sacro-sciatic  ligament,  side  of  sacrum  and 
coccyx,  and  posterior  superior  spine.  The  only  opening  in 
it  is  the  SAPHENOUS  OPENING,  formed  by  splitting  and  crossing 
of  its  upper  extremity,  and  covered  by  the  thin  cribriform 
fascia.  Of  the  two  portions  formed  by  this  split,  the  outer 
iliac  portion  covers  the  sartorius  and  ilio-psoas,  and  is  inserted 
into  the  whole  length  of  Poupart,  while  the  inner  pubic  portion 
covers  the  adductor  longus  and  pectineus,  and  is  inserted 
deeply  behind  the  femoral  vessels  to  the  ilio-pectineal  line, 
fusing  with  the  fascia  iliaca  as  it  does  so.  It  is  not  of  uniform 
strength,  the  thickest  portion  being  the  ilio-tibial  band  on  the 
outer  side,  and  it  sends  in  septa  between  the  muscles,  of  which 
the  most  important  are  the  internal  and  external  intermuscular 
septa,  the  former  extending  from  the  lesser  trochanter  to  the 
adductor  tubercle,  and  the  latter  lying  beneath  the  great 
trochanter,  and  extending  to  the  outer  aspect  of  the  knee- 
joint.  This  fascia  is  supposed  to  exert  an  influence  in  causing 
femoral  herniae  and  psoas  abscesses  to  turn  upwards  toward 
the  groin,  while,  on  the  other  hand,  it  may  prevent  a  psoas 
abscess  from  pointing  about  the  small  trochanter.  and  cause 
it  to  travel  down  even  to  the  knee  or  lee:. 


LOWER  EXTREMITY  309 

Lying  between  Poupart's  ligament  and  the  innominate  bone 
are  a  number  of  structures  of  surgical  importance.  The  SPACE 
is  rougfcly  triangular  in  shape,  bounded  above  by  Poupart's 
ligament,  externally  by  the  anterior  edge  of  the  ilium,  and 
internally  by  the  horizontal  ramus  of  the  pubis,  ilio-pectineal 
eminence,  and  upper  margin  of  the  acetabulum,  and  is  sub- 
divided into  an  outer  oval  muscular  compartment,  and  an  inner 
compartment  roughly  triangular,  containing  the  vessels,  by 
the  ILIO-PECTINEAL  LIGAMENT.  This  ligament  is  formed  of 
a  band  of  fascia  lata,  which  extends  from  the  deep  surface  of 
Poupart's  ligament,  just  external  to  the  artery,  to  the  ilio- 
pectineal  eminence. 

The  MUSCULAR  COMPARTMENT  contains  the  ilio-psoas 
muscle,  the  iliacus  portion  being  the  more  external,  and  the 
anterior  crural  nerve  lying  in  the  groove  between  the  iliac  and 
the  psoas  portions.  Then,  internal  to  the  ilio-psoas  and  in 
the  INNER  COMPARTMENT,  lie  the  vessels  in  their  sheath,  the 
artery  being  external  to  the  vein,  while  internal  to  the  vein  is 
the  crural  canal.  The  vessels,  together  with  the  termination 
of  the  long  saphenous  vein,  the  anterior  crural  nerve,  crural 
branches  of  the  genito-crural  nerve,  and  the  femoral  lymphatic 
vessels  and  glands,  lie  embedded  in  some  loose  fatty  tissue  in 
a  prismatic  sulcus,  formed  by  the  ilio-psoas  on  the  outer,  and 
the  adductor  longus  and  pectineus  on  the  inner  side. 

The  FEMORAL  SHEATH,  composed  of  fascia  transversalis  in 
front  and  fascia  iliaca  behind,  invests  the  vessels  for  a  distance 
of  about  ij  inches  beyond  Poupart's  ligament,  and  is  divided 
by  slight  septa  into  three  compartments,  of  which  the  outer 
contains  the  artery,  the  middle  the  vein,  and  the  internal  forms 
the  CRURAL  CANAL.  The  latter  contains  some  fatty  tissue, 
and  one  or  two  lymphatic  glands  and  lymphatic  vessels. 

The  FEMORAL  ARTERY  lies  midway  between  the  anterior 
superior  spine  and  the  symphysis,  and  is  very  superficial.  It 
is  therefore  easily  compressed,  immediately  under  Poupart's 
ligament  against  the  subjacent  pubis  and  hip  capsule,  and 
toward  the  apex  of  Scarpa's  triangle  against  the  shaft  of  the 
femur,  which  lies  rather  to  its  outer  side.  On  the  other  hand, 
the  vessel  is  liable  to  injury,  which  sometimes  causes  arterio- 
venous  aneurism,  when  both  vein  and  artery  are  involved,  and 
it  has  been  opened  by  ulcer ative  processes.  The  common 
femoral  is  not  infrequently  the  seat  of  aneurism,  the  exposed 


310  SURGICAL  ANATOMY 

position  and  the  relationship  to  the  hip-joint  exposing  it  to 
injury,  while  it  soon  breaks  up  into  two  large  trunks. 

The  line  of  the  femoral  artery  in  the  thigh  is  from  a  point 
midway  between  the  anterior  superior  spine  and  the  symphysis 
to  the  adductor  tubercle,  when  the  limb  is  slightly  flexed  and 
rotated  outwards.  If  this  line  be  divided  into  three  equal 
portions,  the  first  represents  so  much  of  the  artery  as  lies  in 
Scarpa's  triangle,  and  the  second  that  which  lies  in  Hunter's 
canal.  The  common  femoral  artery  may  be  ligatured  just 
below  Poupart's  ligament,  or  the  superficial  femoral,  at  the 
apex  of  the  triangle,  the  bifurcation  taking  place  about 
ij  inches  below  Poupart.  The  COMMON  FEMORAL  is  not  often 
ligatured,  as  gangrene  from  want  of  blood-supply  is  apt  to  be 
caused.  The  limb  having  been  adducted  and  rotated  out- 
wards, and  the  line  of  the  artery  noted,  a  vertical  incision, 
commencing  over  Poupart's  ligament  and  extending  down 
some  3  inches,  is  made  through  skin,  fascia,  and  fascia  lata, 
the  femoral  sheath  exposed,  the  arterial  compartment  opened, 
and  the  ligature  passed  from  within  outwards.  Collateral 
circulation  is  established  through  the  gluteal,  sciatic,  arid 
obturator  of  the  internal  iliac,  and  the  deep  circumflex  iliac 
of  the  external  iliac,  with  branches  of  the  profunda,  and  by 
the  internal  pudic  of  the  internal  iliac,  with  the  superficial  and 
deep  external  pudic  of  the  common  femoral.  The  PROFUNDA, 
or  deep  femoral  artery,  is  given  off  about  i^  inches  below 
Poupart,  and  it  in  turn  gives  off  external  and  internal  circum- 
flex, and  perforating  branches. 

The  SUPERFICIAL  ARTERY  is  much  more  frequently  ligatured 
at  the  apex  of  Scarpa's  triangle,  the  circulation  being  main- 
tained by  the  profunda  and  its  branches.  The  limb  being 
placed  as  above,  a  3-inch  incision  is  made  in  the  course  of  the 
artery,  commencing  about  2\  inches  below  Poupart,  through 
skin,  fascia,  and  fascia  lata,  the  long  saphenous  vein  being 
avoided  if  near  the  incision.  The  sartorius  muscle  is  now 
drawn  outwards,  the  sheath  of  the  vessels  exposed  and  opened, 
the  internal  cutaneous  branch  of  the  anterior  crural  nerve 
being  drawn  to  one  side,  and  the  vessel  ligatured.  The  vein 
is  here  a  posterior  relation,  and  the  long  saphenous  nerve  and 
nerve  to  the  vastus  internus  are  external  relations.  The 
collateral  circulation  is  maintained  by  the  above-mentioned 
branches  of  the  iliacs  with  the  profunda  branches,  and  in 


LOWER  EXTREMITY  311 

addition  by  branches  of  the  profunda  with  the  popliteal  and 
its  branches. 

A  reughly  applied  tourniquet  may  cause  phlebitis  of  the 
femoral  vein  (and  neuralgia  of  the  anterior  crural  nerve). 
Phlebitis  is  said  also  to  have  been  caused  by  violent  flexion  of 
the  thigh.  A  slight  dilatation  of  the  upper  part  of  the  femoral 
vein  overlapping  the  crural  canal  is  not  infrequent,  and, 
giving  an  impulse  on  coughing,  may  lead  to  a  diagnosis  of 
femoral  hernia. 

The  long  saphenous  vein  is  sometimes  varicosed  close  up  to 
the  saphenous  opening,  and  is  not  infrequently  ligatured  a 
little  below  this  point  in  severe  cases  of  varicose  veins  of  the 
leg.  It  is  said  that  this  operation  has  been  followed  by 
thrombosis  of  the  femoral  vein,  and  even  of  the  external 
iliac  vein.  The  anterior  crural  nerve  may  be  affected  by 
superficial  injuries,  and  sometimes  in  psoas  abscess.  The 
genito-crural  nerve  supplies  the  cremaster  muscle  and  also 
the  skin  of  Scarpa's  triangle.  Irritation  of  the  skin  in 
this  region  causes  retraction  of  the  testicle,  especially  in 
children,  and  this  reft  ex  is  used  to  test  the  condition  of  the 
second  lumbar  segment  of  the  cord. 

Of  the  MUSCLES,  the  ILIO-PSOAS  is  of  particular  importance 
surgically,  on  account  of  its  sheath  directing  the  course  of  the 
pus  in  psoas  abscess,  where  the  spine  is  the  seat  of  disease 
(q.v.).  Being  extended  over  the  hip-joint,  the  muscle  is  some- 
times sprained  in  violent  exercise,  while  a  bursa,  which  lies 
under  the  muscle,  between  it  and  the  thinnest  portion  of  the 
hip  capsule,  may  become  inflamed,  necessitating  flexion  of 
the  hip  to  relieve  it.  This  bursa  may  become  enlarged  in 
chronic  inflammation,  and  inflammatory  processes  in  it  may 
affect  the  pelvis.  Contraction  of  the  ilio-psoas  muscle  and 
consequent  flexion  of  the  hip  may  be  caused  by  renal  and 
caecal  irritation,  appendicular  abscess  especially  when  situated 
in  the  pelvis,  psoas  abscess,  inflammation  of  the  bursa,  and 
hip  disease. 

Rupture  of  the  ADDUCTOR  muscles  is  not  infrequent,  especially 
in  horsemen — rider's  sprain  consisting  of  a  partial  tearing  of 
the  muscle  close  to  its  pelvic  attachment,  which  is  frequently 
accompanied  by  a  considerable  effusion  of  blood,  which  may 
form  a  hard  swelling.  Ossification  sometimes  follows  such 
accidents,  a  bone — rider's  bone — some  i  to  3  inches  in 


312  SURGICAL  ANATOMY 

length,  developing  in  the  tendon  of  the  adductor  longus  or 
magnus. 

The  bturator,  or  adductor  region,  of  the  thigh  lies  deeply 
under  the  base  of  Scarpa's  triangle,  being  limited  by  the  hip- 
joint  externally,  the  pubic  arch  and  the  perineum  internally, 
the  horizontal  ramus  of  the  pubis  above,  and  the  tuber  ischii 
below.  The  OBTURATOR  MEMBRANE  covers  in  the  foramen, 
and  is  covered  externally  by  the  obturator  externus  muscle. 
In  the  upper  and  outer  part  of  the  membrane  is  the  aperture 
constituting  the  OBTURATOR  CANAL,  which,  J  to  J  inch  in 
breadth,  is  directed  downwards,  forwards,  and  inwards.  It 
is  bounded  above  by  the  pubic  ramus,  below  by  the  membrane 
and  the  two  obturator  muscles.  Its  pelvic  orifice  is  overlaid 
by  parietal  pelvic  fascia,  extraperitoneal  tissue,  and  by  the 
distended  bladder,  while  its  orifice  on  the  thigh  opens  on  the 
deep  surface  of  the  pectineus,  slightly  internal  to  the  femoral 
vein.  The  canal  lodges  some  loose  fatty  tissue,  and  is  tra- 
versed by  the  obturator  vessels  and  nerve,  the  artery  occupy- 
ing the  outer  part  of  the  canal,  and  sending  a  branch  to  the 
hip-joint  through  the  cotyloid  notch,  and  supplying  the 
adductor  muscles  The  nerve  arises  from  the  second,  third, 
and  fourth  lumbar  nerves,  divides  into  two  branches  in  the 
canal,  and  sends  a  branch  through  the  cotyloid  notch  to  the 
hip-joint,  supplies,  the  adductor  gracilis  and  obturator  ex- 
ternus, and  sends  a  branch  to  the  knee-joint  (geniculate 
branch) .  A  hernia  may  proceed  through  the  canal,  lie  beneath 
the  pectineus,  and  closely  simulate  a  femoral  hernia  (see 
Hernia).  In  addition  to  the  obturator  externus  and  adductor 
muscles,  the  gracilis  and  pectineus  form  the  mass  of  muscle 
which  occupies  this  region. 

The  HIP-JOINT  is  an  excellent  example  of  a  ball-and-socket 
joint.  Ilium,  ischium,  and  pubis  all  enter  into  the  com- 
position of  the  acetabulum,  and  are  connected  by  a  Y-shaped 
cartilage,  which  begins  to  ossify  about  the  twelfth  year,  and 
has  disappeared  by  the  sixteenth.  Separation,  from  injury, 
of  the  three  anatomical  portions  has  occasionally  occurred 
prior  to  fusion.  The  articular  portion  of  the  acetabulum  is 
roughly  horseshoe-shaped,  about  f  inch  broad,  and  rests 
upon  the  upper  thick  portion  of  the  bone,  which  sends  a 
buttress  up  in  front  of  the  great  sacro-sciatic  notch  to  the 
sacro-iliac  articulation,  and  one  down  from  the  lower  and  back 


LOWER  EXTREMITY 


313 


part  of  the  articulation  to  the  tuber  ischii.  The  projecting 
bony  rim  of  the  acetabulum  is  interrupted  below  by  the 
cotyloidf  notch,  which  is  bridged  by  the  transverse  ligament, 
transmits  the  articular  vessels  and  nerves,  and  leads  to  the 
non-articular  portion  of  the  acetabulum,  which  is  extremely 
thin.  The  weight  of  the  body,  however,  does  not  come  upon 
this  thin  portion,  and  ordinarily  the  head  of  the  femur  does 
not  come  in  contact  with  it  in  any  position.  This  area  is 
occupied  by  some  fatty  tissue,  covered  by  the  synovial  mem- 


FIG.  37.— OUTLINE  DIAGRAM  OF  LONGITUDINAL  SECTION  OF  HIP. 
(After  Braune.) 


1.  Ilio-psoas  with  ant.  crural 

nerve  embedded. 

2.  Glut.  med. 

3.  Glut.  min. 


4.  Obturat.  int. 

5.  Obturat.  ext. 

6.  Adduct.  mag. 


7.  Adduct.  brev. 

8.  Pectineus. 

9.  Gracilis. 


brane.  It  is  frequently  perforated  in  hip  disease  in  children, 
prior  to  soldering  of  the  component  parts,  the  tubercular 
debris  thus  entering  the  pelvis,  passing  up  under  the  obturator 
internus  and  obturator  fascia,  and  appearing  finally  above 
Poupart's  ligament.  It  is  also  possible  for  the  hip-joint  to  be 
invaded  through  this  thin  area  by  pelvic  abscess. 

The  depth  of  the  acetabulum  is  increased  by  the  cotyloid 
ligament,  which  is  attached  all  round  to  its  rim,  like  a  ring  or 
collar,  while  its  free  edge  projects  inward,  encircling  and  grasp- 


314  SURGICAL  ANATOMY 

ing  the  head  of  the  femur,  and  thus  providing  a  practically 
air-tight  joint.  The  spherical  HEAD  OF  THE  FEMUR  is  marked 
by  the  depression  for  the  ligamentum  teres  below  and  behind 
the  summit,  with,  beyond  it,  a  smooth  flattened  area  over 
vyhich  the  ligament  glides.  The  inner  extremity  of  the  liga- 
ment is  attached  to  the  bone  on  each  side  of  the  cotyloid  notch 
and  to  the  transverse  ligament.  The  head  of  the  femur  is 
separated  from  the  neck  by  an  epiphysis,  which  appears  in 
the  first  year,  and  unites  to  the  shaft  about  the  eighteenth  year. 
Sometimes  the  articular  cartilage  of  the  head  is  prolonged 
over  the  anterior  aspect  of  the  neck,  and  a  facet  appears  on 
the  anterior  portion  of  the  acetabular  rim,  where  a  position 
of  flexion  is  frequently  assumed,  as  in  tailors  and  acrobats. 

The  NECK  OF  THE  FEMUR  forms  normally  an  angle  of  125 
degrees  with  the  shaft.  Its  anterior  surface  lies  entirely 
within  the  capsule  of  the  joint,  but  only  the  inner  two-thirds 
of  the  posterior  surface  are  intracapsular.  The  outer  one-third 
of  the  posterior  surface  is  grooved  by  the  tendon  of  the 
obturator  externus  muscle,  which  is  inserted  in  a  depression 
at  the  base  of  the  great  trochanter  (obturator  fossa).  The 
intracapsular  portion  of  the  neck  of  the  femur  is  invested  by 
fibrous  bands,  reflected  from  the  capsule  at  its  insertion, 
which  are  called  the  cervical  ligaments,  and  extend  up  to  the 
junction  with  the  head.  These  extend  especially  from  (a)  the 
middle  of  the  Y-shaped  ligament  ;  (b)  from  the  pectineo- 
femoral  ligament  ;  and  (c)  from  the  upper  and  back  part  of 
the  neck. 

The  GREAT  TROCHANTER  gives  attachment  to  the  gluteus 
minimus  by  its  anterior  margin  ;  the  obturator  intern  us  and 
pyriformis  by  its  upper  margin  ;  the  quadratus  femoris  by 
its  posterior  margin,  and  the  gluteus  medius  by  its  outer 
surface,  the  bursa  separating  it  from  the  gluteus  maximus 
being  situated  just  below  this  point.  The  epiphysis  of 
the  great  trochanter  appears  about  the  second  year,  and 
joins  the  shaft  about  the  eighteenth.  The  great  trochanter 
has  occasionally  been  separated  as  an  epiphysis.  The  tip  of 
the  great  trochanter  lies  nearly  on  a  level  with  the  spine 
of  the  pubis,  and  f  inch  below  the  top  of  the  head  of  the 
femur. 

The  SMALL  TROCHANTER  gives  insertion  to  the  ilio-psoas 
muscle,  and  from  it  three  ridges  diverge — the  posterior  inter- 


LOWER  EXTREMITY  315 

trochanteric  ridge,  a  ridge  along  the  under  surface  of  the  neck 
to  the  head,  and  one  running  vertically  downwards  to  the 
linea  aspera.  The  epiphysis  of  the  small  trochanter  appears 
about  the  fourteenth  year,  and  joins  the  shaft  at  the 
eighteenth. 

The  CAPSULAR  LIGAMENT  is  attached  to  the  rim  of  the 
acetabulum,  the  cotyloid  ligament,  and  the  transverse  liga- 
ment, at  its  pelvic  extremity,  while  on  the  femur  it  is  attached 
in  front  to  the  anterior  intertrochanteric  line,  above  to  the 
junction  of  neck  and  great  trochanter,  posteriorly  to  the 
junction  of  the  middle  and  outer  thirds  of  the  neck,  and 
inferiorly  to  the  lower  border  of  the  neck  near  the  small 
trochanter.  This  capsular  ligament  is  strengthened  by 
certain  limbs,  of  which  the  most  important  is  (a)  the  Y-shaped 
ligament  of  Bigelow,  which  is  inverted,  the  tail  being  inserted 
into  the  anterior  inferior  spine,  and  the  two  bands  near  either 
extremity  of  the  anterior  intertrochanteric  line,  the  thickest 
part  of  the  ligament  being  J  inch  thick.  Extension  is  limited 
by  this  ligament.  The  thinnest  part  of  the  capsular  ligament 
is  inside  the  inner  limb  of  the  Y-shaped  ligament,  just  under 
the  bursa  beneath  the  ilio-psoas  muscle.  Sometimes  the 
ligament  is  wanting  here,  synovial  membrane  and  bursa  being 
in  contact  with  one  another,  (b)  The  pubo-femoral  ligament 
from  the  ilio-pectineal  eminence  to  the  lower  aspect  of  the  neck 
limits  abduction,  (c)  The  ischio- femoral  ligament  from  the 
lower  part  of  the  rim  of  the  acetabulum  becomes  fused  in  a 
portion  of  the  capsule  posteriorly,  called  the  zona  orbicularis. 
This  ligament,  with  the  ligamentum  teres,  limits  adduction 
when  the  limb  is  flexed.  When  the  limb  is  extended,  adduc- 
tion is  limited  by  the  ilio-femoral  ligament  and  upper  part 
of  the  capsule.  Rotation  outwards  and  inwards  with  the 
limb  extended  is  also  limited  by  the  ilio-femoral  ligament, 
while,  when  the  limb  is  flexed,  outward  rotation  is  limited  by 
the  ilio-femoral  and  teres  ligaments,  and  inward  rotation  by 
the  ischio-femoral  ligament.  Flexion  is  only  limited  by  con- 
tact with  the  trunk,  save  when  the  knee  is  extended,  when 
the  hamstring  muscles,  sciatic  nerve,  etc.,  limit  it.  Additional 
stability  is  given  the  joint  by  the  muscles  which  lie  in.  contact 
with  it  :  the  gluteus  minimus  and  rectus  femoris  above  ; 
ilio-psoas  in  front ;  obturator  externus  below  ;  and  pyriformis, 
obturator  internus  and  gemelli,  and  quadratus  femoris  behind  ; 


3i6  SURGICAL  ANATOMY 

while  cohesion  and  atmospheric  pressure  also  aid  greatly  in 
holding  the  surfaces  in  contact. 

The  SYNOVIAL  MEMBRANE  lines  the  inner  surface  of  the 
capsule,  from  which  it  is  reflected  inwards  on  to  the  neck  along 
the  capsular  insertion,  being  separated  from  the  neck  by  the 
cervical  ligaments.  It  is  inserted  at  the  head  round  the 
margin  of  the  articular  cartilage,  which  ends  close  to  the 
epiphyseal  plate  for  the  head.  At  its  acetabular  extremity, 
where  it  also  is  inserted  at  the  margin  of  the  articular 
cartilage,  it  is  reflected  over  the  cotyloid  ligament,  overlies 
the  fat  in  the  non-articular  part,  and  covers  the  ligamentum 
teres.  It  sometimes  communicates  with  the  bursa  lying  under 
the  psoas  on  its  anterior  aspect. 

The  vessels  of  the  joint  are  chiefly  derived  from  the  internal 
and  external  circumflex  and  obturator  arteries. 

The  nerve-supply  of  the  hip-joint  is  (a)  from  the  anterior 
crural  at  the  front,  (b)  from  the  obturator  at  the  lower  and 
inner  part,  and  (c)  from  the  sacral  plexus  and  sciatic  nerve  pos- 
teriorly. In  hip-joint  disease  pain  is  frequently  referred  to  the 
knee,  so  much  so  that  the  condition  of  the  hip  is  not  infre- 
quently overlooked  and  the  knee  alone  complained  of.  It  is 
therefore  interesting  to  note  that  hip  and  knee  have  an  almost 
identical  nerve-supply,  the  knee  receiving  an  anterior  crural 
branch  in  front,  an  obturator  branch  posteriorly,  and  sciatic 
branches  laterally  and  posteriorly.  In  so-called  '  hysterical 
hip,'  the  patient  frequently  simulates  some  forms  of  hip 
disease,  and  it  is  supposed  that  the  origin  of  the  sciatic 
nerve  from  sacral  segments  of  the  cord,  which  also  supply  the 
pelvic  viscera,  may  so  far  account  for  this. 

Fractures  of  the  neck  of  the  femur  may  be  either  INTRA- 
CAPSULAR,  or  so-called  extracapsular.  The  former  generally 
occurs  at  the  junction  of  head  and  neck,  as  a  result  of  slight 
indirect  violence  in  elderly  persons  in  whom  (a)  the  angle 
between  neck  and  shaft  has  diminished  from  160  in  the  child 
to  125  in  the  adult,  or  even  less  ;  and  (b)  there  is  absorption 
or  fatty  degeneration  of  osseous  trabeculce,  and  notably  of  the 
calcar  femorale.  These  trabeculae  run  in  two  series — the  first 
from  the  lower  part  of  the  neck  near  the  small  trochanter  to 
the  upper  part  of  the  head  ;  and  the  second  from  below  the 
great  trochanter  to  the  lower  part  of  the  head,  thus  forming 
together  a  bracket-shaped  arrangement  to  distribute  the 


LOWER  EXTREMITY  317 

weight.  The  culcar  fc  morale  runs  from  near  the  small  tro- 
chanter  to  the  under  surface  of  the  head.  This  fracture  is 
rarely /impacted,  but  when  it  is,  the  narrow  compact  neck  is 
driven  into  the  broad  cancellous  head.  The  head  is  supplied 
with  blood  from  the  neck,  cervical  ligaments,  and  the  ligamen- 
tum  teres,  but  if  the  two  first  sources  of  blood-supply  are  cut 
off,  the  last  is  not  sufficient  to  promote  osseous  union. 

An  EXTRACAPSULAR  FRACTURE  of  the  neck  of  the  femur 
is  anatomically  impossible  in  front,  where  the  capsule  is  in- 
serted into  the  intertrochanteric  line,  but  is  possible  behind. 
Generally  such  fractures  are  extracapsular  behind  and  intra- 
capsular  in  front,  or  even,  owing  to  the  thickness  of  the 
capsule  at  that  part,  intracapsular.  Such  fractures  are 
generally  caused  by  considerable  violence,  occur  usually  in 
males  about  middle  life,  and  impaction  is  common,  the 
contracted  neck  being  driven  into  the  upper  end  of  the  shaft 
and  trochanter,  which  may  be  split  by  it. 

Certain  SYMPTOMS  are  associated  with  both  forms  of  fracture 
of  the  neck  of  the  femur  :  Shortening  is  due  to  the  glutei,  ham- 
strings, adductors,  rectus,  etc.  Eversion  is  due  to  the  weight 
of  the  limb,  the  centre  of  gravity  of  which  lies  to  the  outer 
side  ;  to  the  action  of  the  ilio-psoas,  adductors,  pectineus,  and 
small  rotators  ;  and  to  the  fracture  being  generally  more 
extensive  posteriorly  than  in  front,  owing  to  the  more  fragile 
nature  of  the  bone  posteriorly.  Shortening  is  evidenced  by 
direct  measurement,  by  the  rising  of  the  great  trochanter 
above  Nelaton's  line,  and  by  relaxation  of  the  fascia  lata 
stretching  between  the  trochanter  and  the  iliac  crest.  Short- 
ening is  generally  greater  in  extra-  than  in  intracapsular 
fractures.  A  fulness  is  sometimes  produced  just  under  Pou- 
part's  ligament,  either  by  effused  blood  or  the  broken  frag- 
ments pushing  the~  capsule  forwards. 

Dislocation  of  the  hip  is  generally  due  to  violence,  but  may 
rarely  be  due  to  muscular  action,  while  it  is  a  frequent  sequela 
of  hip  disease,  and  is  not  infrequently  congenital.  The  only 
portion  of  the  acetabulum  which  is  shallow,  and  where  the  rim 
is  deficient,  is  below,  in  the  region  of  the  cotyloid  notch,  and 
here  the  capsule  also  is  rather  weak.  When  the  limb  is 
markedly  abducted,  the  head  of  the  bone  tends  to  glide  out  of 
the  socket,  and  come  against  this  weak  portion  of  acetabulum 
and  capsule  ;  and  if  the  abduction  be  increased,  the  great 


318  SURGICAL  ANATOMY 

trochanter  hitches  on  the  summit  of  the  acetabulum,  acts  as 
a  fulcrum,  and  so  enables  the  head  to  burst  through  the 
capsule  toward  the  thyroid  foramen.  It  is  believed  that  all 
dislocations  of  the  hip  are  produced  when  the  limb  is  in  this 
abducted  position,  and  are  primarily  downwards  ;  the  lower 
part  of  the  capsule  is  torn,  extending  from  about  the  cotyloid 
notch  to  near  the  small  trochanter,  and  thence  along  the  back 
of  the  neck  ;  the  ligamentum  teres  is  torn,  but  the  Y-shaped 
ligament  remains  intact.  Four  typical  forms  of  dislocation 
of  the  hip  are  described,  which,  resulting  from  the  original 
downward  displacement,  depend  largely  upon  the  character 
of  the  dislocating  force  and  upon  the  intact  Y-shaped  ligament. 

The  most  common  dislocation  of  the  hip  is  that  backwards 
ON  TO  THE  DORSUM,  and  is  produced  by  a  position  of  flexion 
and  internal  rotation  of  the  thigh  on  the  pelvis,  assisted 
perhaps  by  the  glutei,  hamstring,  and  adductor  muscles.  The 
head  of  the  bone  lies  on  the  dorsum  above  the  tendon  of  the 
obturator  internus.  The  limb  is  shortened ;  it  is  flexed, 
adducted,  and  rotated  inwards,  abduction  and  rotation 
outwards  being  impossible  ;  the  ilio-psoas  is  much  stretched, 
and  the  quadratus  femoris,  pyriformis,  obturator,  and  gemelli 
lacerated,  even  the  pectineus  and  glutei  frequently  suffering, 
while  the  great  sciatic  nerve  may  be  compressed.  The  flexion 
is  due  to  tension  upon  the  Y-shaped  ligament  and  ilio-psoas, 
the  adduction  and  inversion  to  the  altered  position  of  the 
head,  the  Y-shaped  ligament  remaining  intact.  The  gluteal 
fold  is  raised,  the  depression  behind  the  great  trochanter  is 
obliterated,  and  the  head  may  appear  as  a  fulness  of  the 
buttock.  Dislocation  BACKWARDS  on  to  the  ischium  is  similar 
in  mode  of  production  and  symptoms  to  the  former,  the  flexion 
and  inward  rotation  at  the  time  of  production  being  more 
marked,  while  the  head  ultimately  lies  on  the  ischium  near  the 
spine,  and  below  the  tendon  of  the  obturator  internus.  This 
form  is  sometimes  referred  to  as  dislocation  into  the  sciatic 
notch  ;  it  is  doubtful  if  such  a  displacement  ever  occurs. 

Dislocation  into  the  OBTURATOR  FORAMEN  (THYROID)  is 
produced  where  the  head  maintains  its  primary  position,  or 
moves  slightly  forwards.  If,  on  the  other  hand,  extension 
and  external  rotation  are  present,  the  head  may  slip  forward, 
and  lie  on  the  pubic  ramus  in  front  of  the  ilio-pectineal 
eminence,  producing  a  dislocation  ON  TO  THE  PUBIS.  In  these 


LOWER  EXTREMITY  319 

forms  the  limb  is  flexed,  abducted,  and  everted.  In  the 
obturator  form  the  position  is  maintained  by  the  ilio-psoas 
and  the*' Y-shaped  ligament  ;  in  the  pubic  form  the  abduction 
and  eversion  is  chiefly  due  to  the  position  of  the  head  of  the 
bone,  the  Y-shaped  ligament  remaining  intact,  while  the 
flexion  is  due  chiefly  to  tension  of  the  ilio-psoas.  In  these 
forms  the  adductors,  gracilis,  and  pectineus  muscles  are 
frequently  lacerated,  while  the  ilio-psoas,  pyriformis,  and 
glutei  muscles  are  stretched.  The  obturator  nerve  may  be 
stretched  or  torn,  and  in  the  pubic  form  the  anterior  crural 
nerve  may  suffer.  In  the  pubic  dislocation  there  is  slight 
shortening  of  the  limb,  while  in  the  obturator  there  is  apparent 
lengthening  due  to  tilting  of  the  pelvis  down  on  the  injured 
side. 

In  REDUCING  these  dislocations,  the  limb  is  (i)  flexed  fully 
upon  the  abdomen  so  as  to  relax  the  Y-shaped  ligament,  and, 
further,  to  disengage  the  head  of  the  bone.  This  flexion  is 
combined  with  marked  adduction  in  the  first  two  forms,  and 
with  marked  abduction  in  the  two  latter.  In  other  words, 
one  first  increases  the  deformity  in  all  cases.  (2)  In  order  to 
bring  the  head  of  the  bone  back  to  the  position  of  the  rent  in 
the  capsule,  the  limb  is  circumducted  out  in  the  first  two  forms, 
and  circumducted  in  in  the  two  latter.  (3)  To  make  the  limb 
re-enter  the  acetabulum,  the  limb  is  extended  in  all  cases. 
Much  depends  in  all  cases  in  getting  the  muscles  relaxed,  and 
in  making  the  flexion  of  the  thigh  on  the  pelvis  as  full  as  possible. 
In  addition  to  the  action  described  above,  this  movement 
hitches  the  upper  end  of  the  femur  against  the  pelvis,  and  so 
lifts  the  head  of  the  femur  on  to  a  level  with  the  acetabulum, 
which,  it  will  be  remarked,  presents  a  raised  margin  externally 
as  well  as  internally.  It  is  sometimes  useful  to  remember  that 
the  internal  condyle  faces  nearly  in  the  same  direction  as  the 
head  of  the  bone. 

CONGENITAL  DISLOCATION  of  the  hip  is  fairly  common, 
especially  in  females.  While  the  dislocation  is  generally  of 
the  dorsal  type,  it  differs  from  a  traumatic  dislocation  in 
certain  important  particulars :  The  acetabulum  is  rudi- 
mentary, its  surface  being  covered  by  fibrous  tissue  instead  of 
articular  cartilage  ;  the  ligamentum  teres  may  be  absent,  or, 
when  present,  is  wider  and  longer  than  normal  ;  the  capsule  is 
elongated,  and  its  upper  part,  which  bears  the  weight  of  the 


320  SURGICAL  ANATOMY 

limb,  is  thickened,  resembling  fibre-cartilage.  The  head  of 
the  femur  is  smaller  than  normal  and  rather  pointed,  and  the 
neck  is  short  and  directed  straight  forwards,  instead  of  for- 
wards and  inwards  as  it  is  normally.  The  head  generally  lies 
to  the  outer  side  of  the  anterior  inferior  spine  of  the  ilium,  while 
the  great  trochanter  is  directed  backwards,  but,  in  children 
at  least, the  head  possesses  a  considerable  range  of  movement 
in  an  up-and-down  direction,  producing  a  characteristic  gait. 
The  limb  is  generally  quite  straight  and  shortened  ;  the  great 
trochanter  is  situated  posterior  to  instead  of  in  front  of  the 
head,  and  above  Nelaton's  line,  forming  a  prominence  in  the 
gluteal  region.  As  the  trunk  has  a  tendency  to  fall  forward, 
owing  to  gravity  now  falling  in  front  of  the  axis  of  the  bone, 
the  shoulders  are  thrown  back,  there  is  marked  lordosis,  and 
the  hips  are  prominent. 

Hip- Joint  Disease. — The  hip  is  often  affected  by  tubercle, 
especially  in  children,  and  is  less  frequently  attacked  by 
rheumatoid  arthritis.  As  the  joint  is  deeply  placed,  evidence 
of  swelling  in  the  joint  is  not  an  early  symptom,  and  it  is 
generally  late  in  the  disease  before  the  tubercular  debris  makes 
an  exit  externally.  Pain  also,  as  already  pointed  out,  is  often 
referred  to  the  knee,  the  hip- joint  being  sometimes  entirely 
overlooked.  Hip  disease,  therefore,  in  the  early  stages,  is,  to 
a  considerable  extent,  diagnosed  by  the  position  of  the  limb, 
and  its  limited  power  of  movement,  and  it  should  be  remem- 
bered that  it  is  not  always  easy  at  a  very  early  stage  to 
differentiate  between  hip  disease  and  psoas  abscess.  When 
the  hip- joint  is  affected,  the  patient  places  the  limb  in  the 
position  of  greatest  ease,  and  keeps  it  there,  as  far  as  possible, 
without  movement  with  reference  to  the  pelvis.  When  the 
hip- joint  is  fixed,  the  limb  may  still  be  moved  in  various 
directions  by  means  of  the  spine,  and  thus  the  superficial 
observer  is  easily  deceived  as  to  the  fixity  of  the  joint.  Hip 
disease  is  generally  said  to  present  certain  stages,  and  they 
are  at  least  convenient  as  a  means  of  describing  the  disease. 

i.  In  the  first  stage  effusion  of  fluid  has  occurred  in  the 
joint  ;  all  the  ligaments  are  intact,  and,  in  order  to  accommo- 
date this  fluid,  the  patient  fixes  the  hip- joint  in  a  position  of 
(a)  flexion  and  (b)  abduction  (also  external  rotation),  which 
is  that  of  the  greatest  capacity  of  the  joint.  In  order  to  walk 
he  disguises  this  position  by  (a)  producing  a  lordosis  curve  of 


LOWER  EXTREMITY  321 

the  spine,  thereby  tilting  the  pelvis  downwards,  and  so 
obliterating  the  flexion  ;  (b)  producing  a  scoliosis  curve  of  the 
spine,  thereby  tilting  the  pelvis  down  on  the  affected  side,  and 
so  obliterating  the  abduction.  Thus  this  patient,  while 
keeping  his  hip- joint  flexed  and  abducted  on  the  pelvis,  walks 
with  a  limb  which  is  apparently  straight  and  parallel  to  its 
neighbour  by  means  of  a  lordosis  and  scoliosis  of  his  spine. 
Owing,  however,  to  the  tilting  downwards  of  the  pelvis  on  the 
affected  side,  the  limb  appears  longer  than  its  neighbour,  and 
this,  therefore,  is  referred  to  as  the  stage  of  apparent  lengthening. 

2.  The  effusion  of  fluid  remaining  present,  but  the  ligaments 
becoming  affected,  while  the  adductor  muscles  become  reflexly 
irritated    through    the   obturator   nerve,   the  hip-joint  next 
assumes  a  position  of  (a)  flexion  and  (b)  adduction.     Here  the 
flexion  is  corrected  as  before,  while  the  adduction  is  corrected 
by  a  scoliosis  curve  of  the  spine  in  a  direction  opposite  to  the 
previous  one,  so  that  the  pelvis  is  now  tilted  up  on  the  affected 
side.     Thus  the  limb  again  appears  straight,  but,  owing  to 
the  tilting  of  the  pelvis,  shorter  than  its  neighbour,  and  so  this 
period  is  referred  to  as  that  of  apparent  shortening. 

3.  In  the  late  stages  of  the  disease  either  (a)  a  pathological 
dislocation  of  the  head  on  to  the  dorsum  or  (b)  destruction  of 
the  head  occurs.     In  both  cases  there  is  shortening,  and  this 
stage  is  therefore  referred  to  as  that  of  actual  shortening, 
(a]  Here  the  limb  becomes  fixed  in  a  position  of  flexion  and 
adduction,  which  the  patient  conceals  as  in  (2).     (b)  Here  the 
limb  frequently  is  straight  and  perhaps  everted,  the  condition 
being  practically  that  of  pathological  fracture  of  the  neck  of 
the  femur. 

The  debris  from  tubercular  hip  disease  may  make  its  escape 
in  various  directions.  While  it  sometimes  causes  a  fulness 
under  the  femoral  vessels  close  to  Poupart's  ligament,  it 
generally  escapes  from  the  posterior  portion  of  the  joint,  and 
then  may  work  its  way  forward  between  the  gluteus  minimus 
and  the  bone  and  point  in  front  of  the  great  trochanter,  or 
may  make  its  way  backwards  and  point  in  the  gluteal  region. 
When  it  does  escape  from  the  capsule  in  front,  it  may  enter 
the  sheath  of  the  ilio-psoas,  or,  if  it  escapes  through  the 
acetabulum,  it  may  work  its  way  up  under  the  obturator  and 
iliac  fascia,  and  so  point  above  Poupart's  ligament.  In  either 
of  these  cases  it  might  lead  to  confusion  with  real  psoas  abscess. 

21 


322  SURGICAL  ANATOMY 

Where  the  disease  in  the  hip- joint  has  led  to  extensive 
destruction  of  cartilage,  excision  of  the  hip-joint  is  performed. 
This  is  best  done  through  a  single  incision  in  the  line  of  the  limb 
when  flexed  and  adducted,  made  just  above  the  great  tro- 
chanter  down  on  to  the  head  of  the  bone.  The  capsule  is  thus 
only  split  at  one  point,  the  head  of  the  bone  removed  by  a  fan- 
shaped  osteotome,  the  cut  neck  is  rounded  off,  all  debris 
removed  from  the  acetabulum,  and  the  limb  put  up  in  a 
position  of  abduction  and  extension.  The  abduction  fixes 
the  cut  neck  against  the  acetabulum,  thus  facilitating  fibrous 
union  between  the  two  surfaces.  The  operation  as  performed 
for  disease  is  easy  and  quickly  done,  and  excellent  results  as 
regards  subsequent  movement  are  obtained  when  an  operation 
is  done  at  a  comparatively  early  stage  of  the  disease. 

Amputation  at  the  hip  is  best  performed  by  a  racket  incision, 
which  commences  about  2  inches  above  the  great  trochanter, 
runs  down  over  it  for  about  6  inches,  and  is  then  made  to 
encircle  the  limb  skin  deep.  The  muscles  surrounding  the 
great  trochanter  are  next  divided  on  either  side,  the  hir> joint 
exposed  and  opened,  the  ligamentum  teres  divided,  the  head 
of  the  bone  forced  out,  and  kept  out  by  introducing  a  pad  of 
gauze  into  the  acetabulum.  The  muscles  are  then  divided 
circularly,  and  the  limb  removed  (Jordan's  amputation). 
Bleeding  is  controlled  by  the  shut  fist  of  an  assistant  placed 
over  the  termination  of  the  abdominal  aorta,  the  assistant 
standing  on  a  stool  and  leaning  the  weight  of  his  body  on 
it  through  his  straight  arm  (Macewen) .  The  muscles  divided 
are  the  adductors,  hamstrings,  quadriceps,  sartorius,  tensor 
fasciae  femoris,  ilio-psoas,  pectineus,  glutei,  obturator,  gemelli, 
and  pyriformis.  If  the  muscles  be  stitched  together  after  the 
amputation,  a  remarkably  mobile  stump  is  obtained.  The 
vessels  which  require  ligature  are  the  femoral  and  profunda, 
the  circumflexes  and  branches  from  them  and  from  the 
sciatic,  and  the  first  perforating  of  the  profunda.  The 
nerves  divided  are  the  anterior  crural,  external  cutaneous, 
and  obturator  branches  in  front,  and  the  sciatic  nerves 
behind. 

THE  THIGH — SURFACE  ANATOMY.— Running  from  the  apex 
of  Scarpa's  triangle  to  the  internal  condyle  of  the  femur  is  a 
shallow  groove,  which  lodges  the  sartorius  muscle  and  corre- 
sponds to  the  position  of  the  femoral  artery  in  Hunter's  canal, 


LOWER  EXTREMITY  323 

and  marks  the  separation  between  the  vastus  internus  on  the 
outside, >  and  the  adductor  longus  and  magnus  on  the  inside. 
The  sarrorius  also  forms  the  inner  margin  of  a  triangle,  whose 
apex  is  at  the  anterior  superior  spine  and  whose  outer  border 
is  formed  by  the  tensor  fasciae  femoris,  the  floor  being  formed 
by  the  rectus.  As  the  knee  is  approached,  the  rectus  in  front 
and  vasti  on  either  side  become  particularly  prominent.  The 
position  of  the  external  intermuscular  septum,  which  extends 
in  from  the  fascia  lata  to  the  linea  aspera  of  the  femur, 
separating  the  flexor  and  extensor  muscles,  is  marked  by  a 
slight  vertical  groove  on  the  outer  posterior  aspect  of  the  thigh, 
which  extends  from  the  insertion  of  the  gluteus  maximus  to 
the  outer  side  of  the  knee-joint.  The  skin  over  this  line  is 
rather  adherent  to  the  fascia  lata,  and  in  front  of  it  the  tissues 
do  not  yield  readily  to  pressure,  owing  to  the  ilio-tibial  band. 
The  course  of  the  long  saphenous  vein  is  indicated  by  a  line 
running  from  the  saphenous  opening  to  the  posterior  border 
of  the  sartorius  at  the  level  of  the  internal  condyle  ;  that  of  the 
long  saphenous  nerve  by  the  line  of  the  artery,  the  nerve  lying 
at  first  outside,  and  then,  in  Hunter's  canal,  crossing  in  front 
of  the  femoral  shsath  to  the  inside.  The  course  of  the  great 
sciatic  nerve  is  indicated  by  a  line  from  a  point  midway 
between  the  great  trochanter  and  tuber  ischii  to  the  middle 
of  the  popliteal  space. 

The  SKIN  of  ths  thigh  is  thin  on  the  inner,  but  thicker  on  the 
outer  aspect  of  the  limb,  while,  with  the  exception  of  the 
portion  over  the  external  intermuscular  septum,  it  is  loosely 
attached,  becoming  easily  separated  by  injury  or  in  amputa- 
tion, and  permitting  extensive  subcutaneous  extravasations. 
The  FASCIA  LATA,  with  the  ilio-tibial  band  and  external  inter- 
muscular septum,  has  already  been  spoken  of.  In  all  it  sends 
in  three  septa,  separating  the  muscles  into  three  distinct 
groups — anterior,  flexor,  and  adductor.  The  extensor  group 
is  supplied  by  the  anterior  crural  nerve,  the  flexor  group  by  the 
great  sciatic  nerve,  and  the  adductor  group  by  the  obturator 
nerve.  Both  external  and  internal  septa  extend  into  the 
linea  aspera.  The  former,  commencing  at  the  insertion  of  the 
gluteus  maximus  beneath  the  great  trochanter,  ends  at  the 
knee-joint,  and  separates  the  extensor  from  the  flexor  muscles 
(vastus  externus  from  short  head  of  biceps),  while  the  latter, 
less  well  defined,  extends  from  the  small  trochanter  to  the 

21 — 2 


324 


SURGICAL  ANATOMY 


adductor  tubercle,  and  separates  the  extensors  from  the 
adductors  (vastus  internus  from  the  adductor  longus  and 
magnus).  A  third  ill  -  defined  septum  sepaiates  the  ad- 
ductors from  the  flexors.  At  the  knee  the  fascia  extends  down 
in  front  over  the  quadriceps  and  patella,  and  becomes  con- 
tinuous with  the  deep  fascia  of  the  leg,  while  posteriorly  it 
covers  in  the  popliteal  space,  and  surrounds  the  muscles 
forming  its  lateral  boundaries.  The  fascia  lata  offers  resist- 
ance to  all  swellings  lying  under  it.  It  has  occasionally  been 
ruptured  by  injury,  and  the  subjacent  injured  muscle  (quadri- 


1?     ;.e 


FIG.   38. — OUTLINE  DIAGRAM  OF  TRANSVERSE  SECTION  OF  THIGH  AT 
THE  JUNCTION  OF  UPPER  AND  MIDDLE  THIRDS. 

(ModiEed  from  Heath.) 


1.  Tensor  fasciae  femorU. 

2.  Rectus. 

3.  Sartorius. 

4.  Vastus  externus. 

5.  Vastus  int.  and  crureus. 
6    Adduct.  long. 

7.  Pectineus. 

8.  Adduct.  brev. 


9.  Adduct.  gracilis. 

10.  Adduct   magnus. 

11.  Semimemb. 

12.  Semitend. 

13.  Biceps. 

14.  Ext.  cutan.  nerve. 

15.  Femoral  vessels. 


16.  Profunda  vessels. 

17.  Small  sciatic  nerve. 

1 8.  Great  sciatic  nerve. 

19.  Superficial  obturator  nerve. 

20.  Deep  obturator  nerve. 

21.  Ext.  circumflex  vessels. 

22.  Ant.  crural  nerve. 


ceps,  or  adductor  longus)  has  formed  a  hernia  through  the  rent. 
The  quadriceps  tendon  has  been  ruptured  by  muscular  violence. 
Hunter's  canal  lies  on  the  inner  side  of  the  thigh,  occupying 
fully  the  middle  third  of  the  line  already  given  as  representing 
the  course  of  the  femoral  artery,  the  upper  third  of  which  lies 
in  Scarpa's  triangle.  It  consists  of  a  narrow  prismatic  space, 
bounded  externally  by  the  vastus  internus  and  internally  by 
the  adductors  longus  and  magnus,  and  roofed  in  by  a  strong 
fibrous  expansion  running  from  the  vastus  to  the  adductors. 
It  contains  the  superficial  femoral  vessels,  the  vein  lying  behind 


LOWER  EXTREMITY  325 

and  a  little  to  the  outside  of  the  artery,  and  the  long  saphenous 
nerve,  which  lies  in  front  of  the  vessels,  running  obliquely 
from  without  inwards. 

In  LIGATURE  OF  THE  ARTERY,  in  Hunter's  canal,  the  limb 
is  flexed,  abducted,  and  rotated  outwards,  and  an  incision 
made  in  the  middle  one-third  of  the  thigh  through  the  skin, 
subcutaneous  tissue,  and  deep  fascia,  the  long  saphenous  vein 
being  drawn  to  one  side  if  exposed  ;  the  sartorius,  whose  fibres 
may  be  recognized  running  down  and  inwards  (while  those  of 
the  vastus  internus  run  down  and  out),  is  drawn  inwards 
(opposite  of  its  treatment  in  Scarpa's  triangle),  and  then  the 
aponeurotic  roof  of  the  canal  is  incised,  the  long  saphenous 
nerve  drawn  to  the  side,  and  the  ligature  passed  from  either 
side.  The  collateral  circulation  is  the  same  as  in  ligature  at 
the  apex  of  Scarpa. 

THE  FEMUR. — With  reference  to  operations  on  and  frac- 
tures of  the  femur,  it  should  be  remembered  that  the  periosteum 
is  much  thicker  in  children  than  in  adults,  so  that  displace- 
ment is  frequently  prevented  by  it  in  children.  The  femoral 
artery  lies  close  to  the  head  of  the  femur,  but  from  that  point 
to  the  lower  end  of  Hunter's  canal  is  separated  from  it  by 
a  considerable  mass  of  muscle,  while  in  passing  through  the 
opening  in  the  adductor  magnus,  and  thereafter  as  the  pop- 
liteal artery,  it  lies  close  to  the  bone.  The  main  nutrient 
artery  enters  the  centre  of  the  shaft  at  the  linea  aspera,  and  a 
second  enters  2  or  3  inches  lower  down.  The  bone  is  inclined 
downwards  and  inwards  from  hip  to  knee,  the  obliquity  being 
greater  in  females,  and  it  is  slightly  curved,  with  the  convexity 
forwards.  In  section  it  is  triangular  in  the  middle  one-third, 
and  oval  in  the  lower  third.  While  the  bone  is  generally 
deeply  placed  among  the  muscles,  particularly  in  the  upper 
half,  it  lies  entirely  in  the  anterior  half  of  a  transverse  section 
at  the  junction  of  the  middle  and  lower  one-third.  In  this 
region  also  there  are  no  important  vessels  or  nerves  on  the 
outer  side,  and  the  shaft  of  the  bone  is  comparatively  thin  on 
its  outer  surface.  Hence  operations  for  osteomyelitis,  wiring 
ununited  fractures,  etc.,  are  generally  performed  through  this 
outer  aspect.  The  two  lower  limbs  are  very  frequently  of 
unequal  length,  the  left  being  often  the  longer  by  about  J  inch. 
This  difference  is  generally  due  to  the  femur. 

Fractures  of  the  shaft  of  the  femur  may  be  due  to  either 


326  SURGICAL  ANATOMY 

direct  or  indirect  violence,  the  former  most  often  affecting  the 
lower  one-third,  the  latter  the  upper  one-third,  while  the  two 
forms  are  of  equal  frequency  in  the  middle  one-third.  As 
direct  violence  generally  produces  a  transverse,  while  indirect 
produces  an  oblique  fracture,  it  follows  that  fractures  in  the 
lower  one-third  are  generally  transverse,  and  those  in  the 
upper  generally  oblique,  while  oblique  and  transverse  occur 
equally  in  the  middle  one-third.  The  femur  is  rarely  fractured 
by  muscular  violence.  In  oblique  fractures  the  obliquity  is 
from  above,  downwards  and  forwards,  this  obliquity  being 
combined  with  an  inclination  inwards  in  the  upper  one-third. 
In  both  upper  and  middle  one-third  where  the  fracture  is 
oblique,  the  upper  fragment  tends  to  project  forwards  and  a 
little  outwards,  being  pushed  forward  by  the  lower  fragment, 
and  pulled  by  the  action  of  the  ilio-psoas.  This  tilting  forward 
is  most  marked  in  the  upper  one-third.  The  lower  fragment 
is  drawn  up  behind  the  upper  by  the  rectus,  gracilis,  sartorius, 
tensor  fasciae  femoris,  hamstrings,  and  adductors,  the  latter 
also  producing  a  slight  inclination  inwards.  The  lower 
fragment  is  also  generally  everted  by  the  weight  of  the  limb 
and  external  rotators.  Fracture  in  the  lower  one-third 
generally  occurs  about  2  inches  above  the  epiphysis,  at  the 
position  where  compact  shaft  and  cancellous  extremity  meet. 
Where  this  fracture  is  oblique,  and  the  obliquity  favours  the 
displacement,  the  lower  fragment  is  apt  to  be  tilted  backwards 
by  the  gastrocnemius,  and  drawn  up  by  the  hamstrings, 
adductors,  and  other  muscles  mentioned  above,  and  as  the 
femoral  artery  lies  close  to  the  bone  in  this  region  it  is  in  some 
danger  of  being  wounded.  In  such  cases  the  limb  is  best 
treated  in  a  flexed  position,  and  this  position  of  flexion  is 
necessary  in  treating  fractures  of  the  upper  one-third.  Spiral 
fractures  due  to  torsion  forces  are  met  with  in  the  lower  end  of 
the  femur  and  of  the  tibia,  and  are  sometimes  spoken  of  as 
helicoidal  fractures  of  Leriche.  Fractures  of  the  femur  in 
children  are  frequently  transverse,  and,  the  periosteum 
remaining  intact,  no  sensible  displacement  may  occur.  In 
adults  shortening  frequently  occurs  as  a  result,  but  in  estimat- 
ing the  amount  of  this  the  frequent  normal  difference  in  the 
length  of  the  two  limbs  should  be  remembered. 

Genu  valgum,  or  knock-knee,  is  a  deformity  due  to  rickets, 
which    affects   the   lower    third  of    the    femur,  the    shaft   of 


LOWER  EXTREMITY  327 

the  bone  becoming  bent  with  the  convexity  inwards.  In 
consequence  of  this  curve  the  epiphyseal  line  is  tilted,  the 
outer  extremity  being  on  a  higher  level  than  the  inner,  while 
the  internal  condyle  appears  to  be  lengthened  in  a  downward 
direction  owing  to  the  tilting.  When  the  patient  attempts  to 
stand  erect  with  the  legs  straight,  the  head  of  the  tibia  rests 
on  the  uneven  condylar  surfaces,  and  is  therefore  thrown 
outwards,  so  that  he  stands  with  the  knees  touching  or  even 
crossing  one  another,  and  the  feet  wide  apart.  When,  on  the 
other  hand,  he  sits,  the  tibia  rests  on  the  more  posterior 
condylar  surface,  which  is  not  affected  by  the  lateral  tilting, 
and  so  the  deformity  disappears.  A  patient  with  severe  genu 
valgum  makes  use  of  this  method  of  minimizing  the  deformity. 
Instead  of  attempting  to  walk  with  straight  limbs,  which  would 
often  be  so  divergent  as  to  render  walking  impossible,  he 
flexes  both  knees  and  hips,  and  so  diminishes  the  divergence. 
In  operating  on  genu  valgum  the  bone  is  cut  through  by  an 
osteotome,  introduced  through  the  soft  tissues,  at  a  point  a 
finger's  breadth  in  front  of  the  adductor  tubercle  (to  avoid 
the  anastomotica  magna),  and  a  finger's  breadth  above  the 
external  condyle  (that  which  is  tilted  upwards ;  to  avoid  the 
epiphyseal  line) .  A  wedge-shaped  incision  is  made  through  the 
bone  (practically  a  transverse  cut  or  fracture),  the  deformity 
is  fully  corrected,  and  the  limb  put  in  a  splint  until  united. 

GENU  VARUM,  or  bow-leg,  is  a  less  definite  condition  also  due 
to  rickets,  in  which  the  femur  presents  a  curve  with  the 
convexity  outwards,  which  may  involve  the  whole  shaft  or 
only  part  of  it.  The  femoral  curve  is  generally  associated 
with  one  in  the  tibia,  which  in  some  cases  is  principally 
affected. 

AMPUTATION  OF  .THE  THIGH  is  generally  performed,  where 
possible,  in  the  lower  third.  The  skin  flaps  are  cut  long,  are 
easily  raised,  and  retract  markedly.  The  anterior  is  generally 
the  longer.  The  muscles  are  generally  cut  by  a  circular  sweep, 
and  retract  unequally,  the  adductors,  vasti,  and  crureus  being 
limited  in  their  retractive  power  by  their  attachment  to  the 
shaft  of  the  femur.  The  femoral  artery  is  generally  cut  in 
Hunter's  canal,  while  the  profunda,  considerably  reduced  in 
size,  lies  close  to  the  linea  aspera  of  the  femur,  behind  the 
tendon  of  the  adductor  longus.  The  other  vessels  cut  are  the 
descending  branches  of  the  external  circumflex,  lower  per- 


328  SURGICAL  ANATOMY 

forating,  and  long  saphenous  vein.  In  order  to  avoid  splitting 
the  femoral  artery  in  cutting  the  flaps  in  an  amputation  in 
the  middle  third  of  the  femur,  it  is  advised  to  make  them 
slightly  lateral  instead  of  directly  antero-posterior.  Care 
should  be  taken  not  to  include  the  long  saphenous  nerve  in  the 
ligature  of  the  femoral  artery.  The  great  sciatic  nerve  lies 
posteriorly  amidst  the  hamstring  muscles  ;  it  is  best  pulled 
down,  and  cut  short,  to  minimize  risk  of  formation  of  stump 
neuroma.  The  other  nerves  cut  are  branches  of  the  middle 
and  internal  cutaneous  and  muscular  branches  of  the  anterior 
crural,  the  anterior  branch  of  the  external  cutaneous,  the 
obturator,  and  small  sciatic. 

THE  KNEE— SURFACE  ANATOMY. — When  the  leg  is  ex- 
tended it  does  not  lie  in  the  same  line  as  the  thigh,  but,  owing 
to  the  obliquity  of  the  latter,  forms  an  angle  of  about  170 
with  it.  The  patella  is  generally  easily  recognized,  particu- 
larly when  the  limb  is  extended,  its  inner  border  being  more 
prominent  than  the  outer.  In  the  extended  position  it  is 
very  mobile,  and  advantage  may  be  taken  of  this  to  displace 
it  sufficiently  laterally  to  permit  of  examination  of  the  outer 
edge  of  the  external  condyle  and  inner  edge  of  the  internal 
for  evidences  of  lipping,  which  occurs  in  rheumatoid  arthritis, 
etc.  On  either  side  of  the  patella,  and  between  it  and  the 
femoral  condyle,  is  a  depression,  which  in  stout  persons  may 
be  obliterated  by  fat,  which  in  the  extended  position,  with  the 
rectus  relaxed,  may  be  united  to  its  neighbour  by  a  shallow 
depression  along  the  upper  margin,  the  whole  forming  a 
horseshoe,  called  the  peripatellar  depression.  Under  this 
depression  are  situated  the  lateral  and  superior  pouches  of 
synovial  membrane  of  the  joint,  and  when  these  are  distended 
from  any  cause,  the  depression  is  replaced  by  a  swelling, 
roughly  horseshoe  in  shape,  which  may  obliterate  the  patellar 
outline.  When  the  knee  is  flexed,  the  patella  at  first  is  rendered 
prominent,  and  then  sinks  deeply  into  the  intercondyloid 
notch,  where  it  becomes  firmly  fixed,  protecting  the  articula- 
tion, and  assisting  the  tubercle  of  the  tibia  to  bear  the  weight 
of  the  body  in  kneeling.  In  this  flexed  position  the  upper 
portion  of  the  trochlear  surface  of  the  femur  can  be  palpated  ; 
the  condyles  separate  from  the  head  of  the  tibia  and  become 
more  distinct,  and  the  ligamentum  patellae  is  rendered  tense. 
On  the  outer  side  of  the  knee  the  tendon  of  the  biceps  may  be 


LOWER  EXTREMITY  329 

felt  posteriorly,  descending  to  be  inserted  into  the  head  of  the 
fibula,  which  is  about  a  finger's  breadth  below  the  articular 
margiitfof  the  tibia,  and  on  a  level  with  the  prominent  external 
tuberosity  of  the  tibia.  Into  this  latter  is  inserted  the  ilio- 
tibial  band  of  fascia  lata,  which  becomes  very  prominent  when 
the  knee  is  actively  extended.  Immediately  in  front  of  the 
biceps  tendon,  near  its  insertion,  the  upper  part  of  the  external 
lateral  ligament  of  the  knee  may  be  felt  when  the  limb  is  very 
slightly  flexed. 

The  internal  condyle  of  the  femur  is  much  more  prominent 
than  the  external,  and  marking  its  upper  limit,  and  the  position 
of  the  epiphyseal  line,  is  the  adductor  tubercle  into  which  the 
tendon  of  the  adductor  magnus  is  inserted.  Where  any  diffi- 
culty is  experienced  in  finding  the  tubercle,  the  limb  should  be 
forcibly  adducted,  and  the  finger  then  run  down  along  the 
prominent  adductor  tendon  to  the  tubercle.  The  sartorius 
and  the  tendon  of  the  gracilis,  the  former  anterior,  pass  behind 
the  internal  condyle,  and  then  curve  forwards,  to  be  inserted 
into  the  upper  and  inner  surface  of  the  shaft  of  the  tibia. 
As  they  cross  the  joint  the  tendon  of  the  semitendinosus  lies 
close  but  posterior  to  them,  the  interspace  being  occupied  by 
the  long  saphenous  vein  and  nerve,  and  the  superficial  branch 
of  the  anastomotica  magna. 

The  SKIN  of  the  front  of  the  knee  is  dense,  while  the  SUB- 
CUTANEOUS TISSUE  contains  but  little  fat,  and  being  lax 
permits  of  considerable  movement  of  the  skin  when  the  knee 
is  extended.  This  mobility  assists  in  protecting  the  joint 
from  various  injuries,  and  is  utilized  in  certain  operations  on 
the  knee  to  render  the  line  of  incision  very  oblique  by  first 
pulling  down  the  skin  prior  to  incising  it.  Where  the  flexed 
knee  is  struck  over"  the  bone  by  a  blunt  instrument,  a  clean-cut 
wound  may  result.  The  front  of  the  knee  is  supplied  with 
blood  by  the  anastomotic,  four  articular  branches  of  the 
popliteal,  and  anterior  tibial  recurrent,  and  with  nerves  from 
the  third  lumbar  segment ;  and  the  fact  that  the  joint  is  supplied 
by  branches  of  the  same  vessels,  and  with  nerves  from  the 
same  spinal  segment  through  the  obturator  nerve,  is  advanced 
by  some  as  an  argument  in  favour  of  the  application  of  blisters 
to  the  front  of  the  knee  in  various  joint  affections.  The 
superficial  lymphatics  lie  on  the  inner  side,  accompanying  the 
long  saphenous  vein, 


330  SURGICAL  ANATOMY 


OF  FRONT  OF  KNEE.  —  i.  Situated  in  the  subcu- 
taneous tissue  over  the  lower  part  of  the  patella  and  upper 
part  of  the  ligamentum  patellae  is  the  prepatellar  bursa,  which 
is  the  largest  subcutaneous  biirsa  in  the  body.  It  is  fre- 
quently subdivided  by  septa,  sometimes  into  superficial  and 
deep  compartments.  From  its  position  it  is  exposed  to  injury 
and  infection,  giving  rise  to  acute  bursitis,  while  a  chronic 
bursitis  commonly  occurs  from  pressure  of  kneeling,  the  con- 
dition here  being  known  as  housemaid's  knee.  In  the  acute 
form,  if  untreated,  the  bursa  frequently  ruptures,  and  the 
septic  matter  invades  the  subcutaneous  tissues  in  front  of  the 
knee-joint,  the  subsequent  swelling  simulating  a  synovitis  of 
the  knee-joint.  Both  forms  are  generally  painful,  particu- 
larly the  acute,  and  as  the  bursa  lies  in  close  contact  with  the 
patella,  the  infection  has  occasionally  spread  to  the  bone. 

2.  There  is  also  a  small  bursa,  situated  between  the  patellar 
ligament  and  the  head  of  the  tibia.     Above  the  bursa  the 
ligamentum  patellae  rests  on  an  infrapatellar  pad  of  fat,  which 
separates  both  it  and  the  bursa  from  the  synovial  membrane. 
Occasionally,    however,    the   bursa   communicates   with    the 
joint.    This  bursa  is  more  painful  when  inflamed,  owing  to  the 
compression  to  which  it  is  subjected.     The  pad  of  fat  pro- 
jecting from  underneath  the  ligament  might  occasionally  be 
mistaken  for  an  enlarged  bursa. 

3.  A  small  bursa  occasionally  exists  in  front  of  the  tubercle 
of  the  tibia,  and  is  noted  especially  in  those  who  require  to 
kneel  (praetibial  bursa). 

4.  Bursae  exist  between  the  internal  lateral  aspect  of  the 
head  of  the  tibia,  and  (a)  the  sartorius  and  (b)  the  gracilis  and 
semitendinosus,  which  have  one  in  common,  while  (c)  a  bursa 
separates  the  tendon  of  the  gracilis  from  the  sartorius.     These 
bursae,  when  enlarged,  present  an  oval  fluctuant  swelling  in 
the  position  indicated,     (d)  The  semimembranosus  also  lies 
on  a  bursa  close  to  its  insertion  ;  this,  however,  is  a  posterior 
relation. 

5.  A  bursa  exists  between  the  quadriceps  tendon  and  the 
shaft  of  the  femur,  which  sometimes  communicates  with  the 
joint. 

The  posterior  aspect  of  the  knee  is  occupied  by  the  popliteal 
space  —  a  lozenge-shaped  area  —  which  again  may  be  divided 
into  an  upper  femoral  and  a  lower  tibial  triangle.  The  femoral 


LOWER  EXTREMITY  331 

triangle  is  bounded  by  the  biceps  externally,  and  the  semi- 
mem  branosus  and  semitendinosus  internally  (the  former  lying 
under /and  on  the  outer  or  triangular  aspect  of  the  latter). 
The  insertions  of  these  muscles  embrace  the  two  heads  of  the 
gastrocnemius,  which  form  the  boundaries  of  the  tibial  triangle. 
When  examining  the  popliteal  space,  the  knee  should  be 
slightly  flexed  in  order  to  relax  the  superficial  tissues  and 
muscles,  and  then  the  finger  may  detect  the  trangular  area 
at  the  back  of  the  femur  (which  is  often  affected  in  acute 
osteomyelitis),  the  vessels,  nerve,  etc.  The  SKIN  here  is  less 
movable  than  in  front,  and  may  become  markedly  contracted 
by  cicatrices,  resulting  in  flexion  of  the  knee.  Contractions 
forcibly  overcome  have  caused  rupture  of  the  skin  in  this 
region.  The  DEEP  POPLITEAL  FASCIA  is  a  continuation  of  the 
fascia  lata  above,  and  is  continuous  with  the  fascia  of  the  leg 
below.  While  it  does  not  possess  any  bony  attachment  it 
presents  a  firm  unyielding  barrier  to  tumours,  abscesses,  etc., 
which  consequently  are  generally  associated  with  severe  pain. 
Abscesses  may  attain  a  large  size,  containing  over  a  pint  of  pus, 
and,  unable  to  escape,  generally  extend  up  into  the  thigh  or 
down  into  the  leg,  but  may  penetrate  the  popliteal  artery  or 
even  the  joint,  while  pus  may  reach  the  space  from  the  pelvis 
by  following  the  great  sciatic  nerve,  or  from  the  thigh  along  the 
femoral  vessels.  The  popliteal  fascia  is  perforated  near  the 
lower  part  of  the  popliteal  space  by  the  external  or  short 
saphenous  vein  which  runs  up  from  the  outer  side  of  the  foot, 
and  a  lymphatic  gland  generally  lies  near  this  point  under  the 
deep  fascia.  A  varicose  condition  of  the  short  saphenous  vein 
has  been  supposed  to  be  due  to  narrowness  of  its  opening  in 
the  deep  fascia.  The  popliteal  space  is  occupied,  particularly 
in  the  femoral  triangle,  by  fatty  tissue  in  which  the  vessels, 
etc.,  are  embedded. 

The  SCIATIC  NERVE  is  the  most  superficial  of  the  important 
structures.  It  divides  at  the  upper  angle  of  the  space  into 
internal  (tibial)  and  external  (peroneal)  popliteal  nerves. 
The  internal  popliteal  nerve  runs  vertically  downwards  across 
the  space  immediately  below  the  deep  fascia,  and,  as  the 
vessels  run  obliquely  across  the  space,  the  nerve  lies  first  to 
their  outer  and  ultimately  to  their  inner  side,  while  at  the 
level  of  the  intercondyloid  notch  it  lies  directly  superficial  to 
the  vessels.  The  external  popliteal  nerve  runs  along  the  inner 


332  SURGICAL  ANATOMY 

border  of  the  biceps  tendon  to  its  insertion,  under  the  deep 
fascia,  and  then,  entering  a  groove  between  the  soleus  and 
peroneus  longus,  curves  forward  between  the  peroneus  and 
neck  of  the  fibula,  i  inch  below  its  head. 

The  POPLITEAL  ARTERY  enters  the  space  through  the  tendi- 
nous arch  of  the  adductor  magnus,  and  first  lies  on  the  outer 
border  of  the  semimembranosus,  but  then,  inclining  outwards, 
reaches  the  middle  line  at  the  level  of  the  intercondyloid  notch, 
which  mesial  position  it  maintains.  It  is  separated  by  a  little 
fatty  tissue  from  the  posterior  surface  of  the  femur,  and  lower 
down  is  in  close  relationship  to  the  posterior  ligament  of  the 
joint  and  the  fascia  covering  the  popliteus  muscle.  Below 
the  popliteal  space  the  artery  divides  into  anterior  and  pos- 
terior tibial  arteries,  while  in  the  space  it  gives  off  muscular 
branches  to  the  hamstrings,  and  two  large  ones  (inferior  sural) 
to  the  two  heads  of  the  gastrocnemius,  and  five  articular 
branches  to  the  knee-joint. 

The  two  superior  articular  branches  (external  and  internal) 
and  two  inferior  articular  branches  run  round  to  the  front  of 
the  femur  and  tibia  respectively,  where  they  take  part  in  an 
anastomosis  with  the  descending  branch  of  the  circumflex, 
the  anastomotica  magna,  and  with  the  recurrent  branch  of 
the  anterior  tibial.  Together  they  form  three  arches,  one  at 
the  upper  border  of  the  patella,  and  the  other  two  running 
transversely  below  the  ligamentum  patellae,  forming  a  net- 
work surrounding  the  patella.  The  fifth,  the  azygos  branch, 
pierces  the  posterior  ligament,  and  is  distributed  to  the 
synovial  membrane,  crucial  ligaments,  etc.,  of  the  joint.  It 
is  accompanied  by  the  geniculate  branch  of  the  obturator 
nerve,  and  an  articular  branch  of  the  internal  popliteal  nerve. 
The  greater  part  of  the  popliteal  artery  is  covered  by  the 
muscles,  about  i  inch  in  the  centre  being  covered  only  by 
superficial  tissues.  When  the  limb  is  extended,  the  vessel  is 
straight,  but  it  becomes  sinuous  when  the  limb  is  flexed,  and 
its  flow  of  blood  is  practically  stopped  on  acute  flexion. 
Owing  to  its  deep  position  the  vessel  is  rarely  wounded,  but  it 
has  been  wounded  in  the  lower  extremity  of  the  space  from 
the  front,  the  instrument  passing  through  the  interosseous 
space,  and  it  has  been  ruptured  by  external  violence.  Save 
for  the  thoracic  aorta,  this  vessel  is  the  one  most  frequently 
affected  by  aneurism,  due  probably  to  movement  (which,  when 


LOWER  EXTREMITY  333 

excessive,  may  damage  the  inner  and  middle  coats),  to  the 
laxity  and  small  amount  of  support  given  by  the  surrounding 
tissues/and  to  the  vessel  breaking  up  into  large  branches  just 
beyond  this  point.  Such  aneurisms  may  attack  the  bone, 
and  give  rise  to  joint  symptoms  ;  may  press  on  the  nerves ; 
may  impede  the  venous  return  from  interference  with  the 
vein,  or  may  point  posteriorly.  The  vessel  is  best  ligatured 
at  the  upper  and  inner  portion  of  the  space  through  an  incision 
some  4  inches  long,  made  parallel  to  and  just  behind  the 
tendon  of  the  adductor  magnus,  the  limb  being  flexed, 
abducted,  and  rotated  outwards.  The  sartorius  is  drawn 
backwards,  the  adductor  magnus  forwards,  the  semimem- 
branosus  backwards,  and  then  the  vein  is  carefully  detached 
from  the  artery,  and  the  ligature  passed.  The  collateral 
circulation  is  abundant  through  the  descending  branch  of  the 
external  circumflex  with  perforating  of  deep  femoral  and 
anastomotica  magna  of  superficial  femoral,  and  these  again 
with  the  articular  branches  of  the  popliteal  and  tibial 
recurrents. 

Emboli  are  particularly  apt  to  lodge  at  the  bifurcation  of 
the  popliteal,  gangrene  of  the  leg  frequently  following  from 
blockage  of  the  three  main  vessels.  The  vein  possesses  an 
unusually  thick  wall,  and  is  intimately  associated  with  the 
artery,  lying  first  to  its  outer  side,  then  directly  behind,  and, 
finally,  to  the  inner  side.  The  vein  generally  escapes  injury 
from  external  violence,  although  more  superficial. 

The  lymphatic  glands  of  the  space,  some  five  in  number,  lie 
embedded  in  fatty  tissue  in  close  proximity  to  the  vessels, 
with  the  exception  of  one  already  mentioned,  which  lies  close 
to  the  fascia  lata  and  the  short  saphenous  vein.  They  receive 
the  lymphatic  channels  from  the  sole  of  the  foot  and  back  of 
the  leg — those  which  accompany  the  short  saphenous  vein  and 
from  the  anterior  tibial  gland.  The  efferent  vessels  run  to  the 
deep  femoral  glands  within  the  saphenous  opening.  Pop- 
liteal abscess  is  often  due  to  suppuration  of  these  glands.  It 
also  is  frequently  caused  by  osteomyelitis  of  the  lower  end  of 
the  femur,  the  pus  coming  to  the  surface  in  the  region  of  the 
triangular  area  on  the  posterior  surface  of  the  shaft. 

Flexion  of  the  knee-joint  from  disease  of  the  joint  may  in 
part  be  due  to  contraction  of  the  hamstring  muscles  from 
irritation,  the  muscles  being  supplied  from  the  fifth  lumbar 


334  SURGICAL  ANATOMY 

segment  through  the  great  sciatic,  which  also  supplies  the 
joint  in  part.  In  some  cases,  not  merely  flexion,  but  subluxa- 
tion,  may  be  produced  from  drawing  of  the  tibia  backwards. 
On  the  other  hand,  these  muscles  frequently  become  perma- 
nently contracted  in  flexion  of  the  knee,  and  necessitate 
tenotomy.  In  subcutaneous  tenotomy  of  the  biceps  there  is 
risk  of  wounding  the  external  popliteal  nerve,  and  therefore 
it  is  frequently  better  to  do  an  open  operation.  Contraction 
of  the  muscle,  or  putting  it  on  the  stretch  by  extending  the 
leg,  increases  its  distance  from  the  nerve,  while  rendering  the 
tendon  more  superficial,  and  then  the  tenotome  is  introduced 
between  the  nerve  and  the  tendon,  and  the  latter  cut  by 
bringing  the  tenotome  toward  the  skin. 

There  are  numerous  BURS^E  IN  THE  POPLITEAL  REGION  :  (i)  The 
largest  is  situated  between  the  internal  condyle  and  the  inner 
head  of  the  gastrocnemius  and  semimembranosus.  In  adult 
life  it  frequently  communicates  with  the  joint,  and  may  become 
markedly  enlarged,  presenting  a  firm  swelling  on  extension, 
which  may  disappear  on  flexion  with  steady  pressure.  Such 
a  swelling  may  receive  transmitted  impulse  from  the  femoral 
artery,  and  so  resemble  aneurism,  while  it  frequently  inter- 
feres with  the  movements  of  the  joint,  necessitating  removal. 
(2)  A  small  bursa,  between  the  outer  head  of  the  gastrocnemius 
and  the  condyle.  (3)  One  between  the  popliteus  tendon  and 
the  external  lateral  ligament,  not  communicating  with  the 
joint.  (4)  One  between  the  popliteus  tendon  and  the  outer 
tuberosity  of  the  femur,  which  communicates  with  the  joint, 
and  frequently  also  communicates  with  the  tibio-fibular 
articulation,  which  thereby  may  communicate  with  the  knee- 
joint.  (5)  One  between  the  biceps  tendon  and  the  external 
lateral  ligament,  which,  when  enlarged,  may  press  on  the 
peroneal  nerve,  and  cause  pain.  (6)  A  small  one  between  the 
semimembranosus  tendon  and  the  back  of  the  head  of  the 
tibia,  already  mentioned.  It  does  not  communicate  directly 
with  the  joint,  but  may  do  so  indirectly  through  communica- 
tion with  (i). 

THE  KNEE-JOINT,  the  largest  in  the  body,  despite  its 
exposed  position  is  rarely  dislocated  owing  to  its  great 
strength.  This  strength  is  due  chiefly  to  the  muscles,  fasciae, 
and  ligaments,  including  the  internal  ones,  and  to  a  less 
degree  to  the  lateral  breadth  of  the  articulation.  The  move- 


LOWER  EXTREMITY  335 

ment  of  the  knee-joint  is  not  that  of  a  hinge,  but  consists 
rather  of  a  gliding  of  the  head  of  the  tibia  on  the.  femoral 
condytes,  combined  with  rotation,  outwards  in  extension  and 
inwards  on  flexion.  In  full  extension  the  limb  becomes 
locked,  and  no  rotation  is  permitted.  This  position  tends  to 
be  assumed  in  standing,  the  weight  of  the  body  falling  in  front 
of  the  centre  of  the  joint,  and  tending  to  produce  over- 
extension.  In  front  the  quadriceps,  containing  the  patella  and 
ending  in  the  ligamentum  patellae  which  is  attached  to  the 
tubercle  of  the  tibia,  replaces  the  capsular  ligament.  Later- 
ally also  tendinous  expansions  from  the  vasti  reinforce  the 
capsule  which  extends  laterally  from  either  margin  of  the 
patella  and  patellar  ligament,  but  is  non-existent  above  the 
patella,  the  synovial  membrane  being  practically  in  contact 
with  the  quadriceps. 

The  patella  is  developed  in  the  quadriceps  tendon,  the 
ossific  centre  appearing  about  the  third  year,  and  ossification 
being  complete  by  the  fifteenth  year.  Its  anterior  surface  is 
very  superficial,  being  covered  by  skin,  superficial  and  deep 
fasciae,  and  a  thin  expansion  of  the  quadriceps  tendon,  which 
has  an  important  bearing  upon  fracture  of  the  bone.  The 
anterior  surface  is  slighth^  convex,  and  perforated  by  numerous 
vascular  foramina,  the  patella  being  richly  supplied  with 
blood  from  the  anastomotica,  anterior  tibial  recurrent,  and 
inferior  articular  of  the  popliteal,  and  hence  bleeding  freely, 
as  a  rule,  after  fracture. 

The  upper  margin  of  the  bone  is  thick,  the  quadriceps  being 
inserted  into  the  anterior  two-thirds,  while  a  small  portion 
behind  this,  which  is  devoid  of  cartilage,  is  covered  by  synovial 
membrane.  The  lateral  margins  and  apex  are  narrow,  the 
former  receiving  tendinous  insertions  from  the  vasti,  while 
the  apex  gives  insertion  to  the  ligamentum  patellae.  The  tendi- 
nous insertions  of  the  vasti,  also  termed  lateral  patellar 
ligaments,  if  not  ruptured,  play  an  important  part  in  mini- 
mizing separation  of  the  fragments  when  fracture  occurs. 
Save  for  the  small  portion  on  the  posterior  surface  of  the  apex 
which  is  covered  by  synovial  membrane,  the  whole  posterior 
surface  of  the  patella  is  covered  with  articular  cartilage,  and 
is  unequally  divided  by  a  vertical  ridge  into  a  small  internal 
and  large  external  portions,  each  of  which  is  again  divided 
into  three  by  a  couple  of  faint  transverse  ridges,  while  a  seventh 


336 


SURGICAL  ANATOMY 


small  vertical  area  may  be  present  near  the  inner  margin. 
On  section,  both  vertically  and  horizontally  the  patella  is 
roughly  triangular,  and  the  vertical  triangularity  is  of  impor- 
tance in  the  mechanism  of  fracture. 

The  LIGAMENTUM  PATELLA,  some  2  inches  in  length,  is  a 
continuation  of  the  quadriceps  tendon  over  the  front  of  the 
patella,  and  also  is  attached  to  the  apex  of  the  bone,  from 


FIG    39. — SAGITTAL  SECTION  OF  THE  RIGHT  KNEE-JOINT,  VIEWED 
FROM  THE  OUTER  SIDE.     (From  Buchanan's  "  Anatomy.") 


1.  Crureus. 

2.  Subcrureus. 

3.  Suprapatellar  bursa. 

4.  Pouch  of  synovial  membrane  of  knee- 

joint 

5.  Prepatellar  bursa. 

6.  Ligamentum  patellae. 


7.  Ligamentum  mucosum. 

8.  Infrapatellar  pad  of  fat. 

9.  Bursa  beneath  ligamentum  patellae. 

10.  Skin. 

11.  Anterior  crucial  ligament. 

12.  Posterior  crucial  ligament. 

13.  Posterior  ligament. 


which  it  inclines  downwards  and  slightly  outwards,  to  be 
inserted  into  the  lower  part  of  the  tubercle  of  the  tibia,  from 
the  upper  portion  of  which  it  is  separated  by  the  infrapatellar 
bursa,  a  bursa  also  sometimes  existing  between  it  and  the  skin. 
While  the  posterior  surface  of  the  patella  as  a  whole  is  in 
communication  with  the  joint,  a  small  portion  of  the  apex, 
together  with  the  upper  third  of  the  ligamentum  patellae,  is 


LOWER  EXTREMITY  337 

separated  from  the  joint  by  a  pad  of  fat.  The  patella  is  the 
bone  most  frequently  broken  by  muscular  action,  and  the 
majority  of  FRACTURES  OF  THE  PATELLA  are  due  to  muscular 
action,  the  fracture  in  such  cases  being  transverse,  and  about 
the  centre  of  the  bone.  The  accident  frequently  occurs  when, 
in  trying  to  prevent  a  fall  backwards,  the  knee  is  slightly  flexed, 
and  the  quadriceps  acts  violently  upon  the  upper  extremity  of 
the  patella,  while  the  lower  is  held  by  the  ligamentum 
patellae.  As  the  patella  is  only  resting  on  the  prominent 
condyles  by  its  transverse  axis,  it  is  snapped  rather  than  torn 
apart.  Unless  the  expansions  from  the  vasti  are  also  torn, 
the  separation  of  the  fragments  is  slight.  Where  the  fracture 
is  complete,  the  prepatellar  bursa  in  front  is  torn,  and  the 
articular  cartilage  posteriorly,  so  that  the  joint  cavity  is 
opened,  and  communicates  with  the  subcutaneous  bursa.  As 
the  patella  is  a  very  vascular  bone,  a  h&marthrosis  frequently 
occurs,  causing  much  distension  of  the  joint.  Attention  has 
already  been  directed  to  the  expansion  of  the  quadriceps 
tendon  in  front  of  the  bone.  As  the  snapping  of  the  bone 
takes  place,  this  expansion  is  stretched,  and  then  also  snaps, 
the  torn  edges  being  infolded  over  the  broken  ends  to  which 
they  generally  adhere  firmly.  Thus,  although  the  broken 
surfaces  be  brought  into  apposition,  each  has  a  layer  of  fibrous 
tissue  in  front  of  it,  and  it  is  on  this  account  that  fibrous 
instead  of  osseous  union  of  transverse  fractures  of  the  patella 
so  frequently  occurs.  In  these  cases  it  is  necessary  to  cut 
down  and  elevate  the  fibrous  tissue  from  the  broken  surfaces, 
which  will  then  unite  by  bone,  even  if  the  fragments  be  only 
held  by  stout  catgut.  The  tendency  to  separation  of  the 
fragments  is  not  nearly  so  great  as  used  to  be  supposed,  and 
the  fact  that  hsemarthrosis  frequently  occurs  sufficiently 
disposes  of  the  other  old  explanation  of  fibrous  instead  of 
osseous  union  that  the  patella  was  poorly  supplied  with  blood. 
Where  transverse  fracture  of  the  patella  occurs  close  to  the 
apex,  it  is  just  possible  for  the  joint  to  escape. 

Oblique,  or  stellate,  'fractures  of  the  patella  may  be  due  to 
direct  violence  ;  but  in  this  connection  it  should  be  remembered 
that  when  one  falls  on  the  knee,  the  tubercle  of  the  tibia,  and 
not  the  patella,  is  the  part  which  comes  most  readily  in 
contact  with  the  ground. 

Of  the  LATERAL  DISLOCATIONS  of  the  patella,  that  outwards 

22 


338  SURGICAL  ANATOMY 

is  the  more  common,  owing  to  the  tendency  of  the  quadriceps 
when  contracted  to  pull  the  patella  and  ligamentum  patellae 
into^a  straight  line,  instead  of  following  the  angle  formed  by 
the  femur  and  tibia.  Normally  this  tendency  is  corrected  by  the 
prominence  of  the  external  condyle.  The  dislocation  generally 
occurs  when  the  limb  is  extended,  is  due  to  muscular  action, 
and  is  incomplete.  It  is  occasionally  met  with  in  cases  of 
genu  valgum.  A  dislocation  of  the  patella  on  its  edge,  the 
inner  edge  projecting  forwards,  may  also  occur. 

Congenital  absence  of  the  patella  has  occurred,  and  may  be 
associated  with  a  striking  deformity,  genu  recurvatum,  in 
which  the  knees  bend  backwards,  the  child  standing  on  the 
calves  of  its  legs. 

Antero -laterally  the  capsule  of  the  joint  is  strengthened,  in 
addition  to  the  lateral  patellar  ligaments,  by  the  ilio-tibial 
band  of  fascia  lata  externally,  and  the  sartorius  and  semi- 
membranosus  internally.  Laterally  it  is  strengthened  by  the 
lateral  ligaments,  of  which  the  internal  is  flattened,  and  extends 
from  the  tuberosity  of  the  internal  condyle  to  the  upper  end 
of  the  inner  border  of  the  tibial  shaft,  while  it  is  attached 
between  the  bones  to  the  inner  semilunar  cartilage.  It  is 
crossed  superficially  by  the  tendons  of  the  sartorius,  gracilis 
and  semitendinosus,  a  bursa  intervening,  while  the  tendon  of 
the  semimembranosus  extends  beneath  its  lower  and  posterior 
border,  and  still  lower  the  inferior  internal  articular  vessels 
pass  under  it.  The  external  lateral  ligament  is  rounded,  and 
extends  from  the  tuberosity  of  the  external  condyle  to  the 
head  of  the  fibula,  just  in  front,  of  the  styloid  process.  In 
front  of  it  passes  an  expansion  of  the  ilio-tibial  band  ;  the 
tendon  of  the  biceps  splits  to  enclose  it  ;  and  the  tendon  of 
the  popliteus  and  inferior  external  articular  vessels  pass  under 
it.  Posteriorly  the  capsule  is  more  defined,,  extending  from 
the  upper  border  of  the  condyles  and  intercondylar  notch  to 
the  head  of  the  tibia.  It.  is  reinforced  by  an  oblique  posterior 
ligament  (ligament  of  Winslow),  derived  from  the  semi- 
membranosus tendon,  extending  from  the  inner  and  lower 
part  of  the  joint  to  the  outer  condyle.  The  capsule  is  overlaid 
by  the  heads  of  the  gastrocnemius,  and  is  pierced  under  the 
inner  head  by  the  communication  between  the  gastrocnemius 
bursa  and  the  joint,  and  is  also  perforated  by  the  azygos 
vessels  and  popliteus  tendon.  The  internal  ligaments  consist 


LOWER  EXTREMITY  339 

of  the  two  crucial  ligaments,  which  are  attached  below,  in 
front  of,  and  behind  the  tibial  spine,  the  anterior  ascending 
to  the  posterior  and  inner  aspect  of  the  external  condyle,  and 
the  posterior  to  the  anterior  and  external  aspect  of  the  internal 
condyle.  Of  these  ligaments,  the  anterior  resists  extension 
and  inward  rotation,  or  forward  displacement  of  the  tibia. 

The  SEMILUNAR  FIBRO-CARTILAGES,  roughly  triangular  in 
section,  deepen  the  articular  surfaces  on  the  head  of  the  tibia, 
the  base  being  turned  toward  the  capsule  to  which  it  is 
attached,  while  the  free  apex  projects  inwards.  The  lower 
margin  of  the  base  is  attached  to  the  head  of  the  tibia  by 
coronary  ligaments,  and  the  upper  and  lower  surfaces  and  free 
edge  are  covered  by  synovial  membrane.  The  external  forms 
almost  a  complete  circle,  being  attached  in  front  and  behind 
to  the  tibial  spine,  while  the  internal,  forming  barely  a  semi- 
circle, is  attached  in  front  of  and  behind  the  spine,  the  two 
cartilages  being  connected  anteriorly  by  a  transverse  ligament. 
These  cartilages,  and  particularly  the  internal  one,  are  not 
infrequently  DISLOCATED,  or  broken  through,  by  injury, 
especially  a  twist  when  the  limb  is  slightly  flexed,  the  move- 
ment in  rotation  being  said  to  take  place  between  the  semi- 
lunar  cartilage  and  the  tibia.  It  is  also  said  that  external 
rotation  favours  displacement  of  the  internal  cartilage,  and 
vice  versa.  As  a  result  of  the  accident,  the  knee  frequently 
becomes  locked  in  a  flexed  position. 

The  synovial  membrane  lines  the  capsule  of  the  joint, 
and  is  reflected  at  its  insertions  on  to  the  epiphyses  of  the 
bones,  on  which  it  extends  to  the  margins  of  the  articular 
cartilages.  It  covers  the  semilunar  cartilages  and  the  infra- 
patellar  pad  of  fat,  from  which  latter  it  extends  inwards  and 
upwards  to  the  anterior  part  of  the  intercondyloid  notch, 
forming  the  ligamentum  mucosum,  and  also  extends  inwards, 
and  covers  the  crucial  ligaments.  The  ligamentum  mucosum, 
and  the  coverings  of  the  crucial  ligaments,  together  form  an 
incomplete  septum  along  the  intercondyloid  notch,  dividing 
the  joint  into  two  lateral  compartments.  The  so-called 
ligamenta  alaria  are  delicate  lateral  folds,  running  from  the 
ligamentum  mucosum  to  the  margins  of  the  patella.  Superiorly, 
under  the  quadriceps,  the  synovial  membrane  is  not  reflected 
at  once  on  to  the  epiphysis,  but  extends  up  in  front  of  the 
diaphysis,  forming  the  suprapatellar  pouch  to  a  point  fully 

22 — 2 


340  -  SURGICAL  ANATOMY 

i  inch  above  the  upper  margin  of  the  patella,  where  it  fre- 
quently communicates  with  the  subcrureal  bursa  before  it  is 
reflected.  Thus,  in  the  extended  position,  a  wound  in  the 
front  of  the  femur,  2  inches  above  the  upper  border  of  the 
patella,  may  involve  the  joint.  In  flexion  the  pouch  is 
drawn  slightly  downwards.  The  tendon  of  the  popliteus 
muscle  is  in  contact  with  the  membrane  in  its  intra-articular 
portion,  and  through  the  bursa  between  it  and  the  head  of 
the  tibia  the  knee-joint  may  communicate  with  the  superior 
tibio-fibular  joint. 

The  lower  extremity  of  the  femur  ossifies  from  a  single 
centre,  which  appears  before  birth,  and  joins  the  shaft  about 


FIG.  40. — DIAGRAM  OF  KNEE-JOINT  OF  ADOLESCENT. 

Shafts  of  bones  shaded  obliquely ;  epiphyseal  plates  black  ;  articular  cartilages  shaded 
vertically. 

Note  that  periosteum  of  shaft  stops  at  epiphyseal  plate  to  which  it  is  firmly  attached. 

Note  that  synovial  membrane  commences  at  edge  of  articular  cartilage  and  runs  up  over 
epiphysis,  but  is  quite  distinct  and  cut  off  from  the  periosteum  ;  further,  that  it  covers  the 
crucial  ligaments. 

the  twentieth  year.  The  epiphyseal  line  is  roughly  horizontal, 
and  the  adductor  tubercle  forms  a  convenient  guide  to  its 
position,  the  line  running  just  above  the  tubercle.  The  plane 
of  the  articular  surfaces  of  the  femoral  condyles  is  also  hori- 
zontal when  the  femur  is  in  its  normal  position,  with  the  shaft 
extending  downwards  and  slightly  inwards.  The  inner 
condyle  is  the  narrower,  and  anteriorly,  above  the  condyles, 
the  articular  surfaces  coalesce  to  form  the  trochlear  surface, 
which  is  more  prominent,  and  ascends  higher,  on  the  outer  than 
on  the  inner  border.  Over  this  trochlear  surface  the  patella 


LOWER  EXTREMITY  341 

glides.  When  the  limb  is  extended,  the  apex  of  the  patella  is 
just  on  a  level  with  the  upper  surface  of  the  tibia,  and  the 
upper  margin  of  the  patella  reaches  the  level  of  the  epiphyseal 
line.  In  slight  flexion  the  patella  rises  slightly  in  reference  to 
the  head  of  the  tibia,  but  in  relation  to  the  femur  descends  as 
flexion  increases,  till  in  full  flexion  the  articular  surface  of  the 
patella  is  opposite  the  intercondyloid  notch.  In  flexion  the 
bone  is  wedged  against  the  trochlear  surface,  so  that  but  little 
lateral  movement  is  permitted.  The  lower  epiphysis  of  the 
femur  may  be  separated,  or  a  T-shaped  fracture  involving  the 
joint  may  occur,  or  one  or  other  condyle  may  be  separated. 

The  head  of  the  tibia  is  also  developed  from  a  single  centre, 
appearing  shortly  before  birth,  which  joins  the  shaft  about 
the  twenty-second  year.  The  epiphyseal  line  runs  roughly 
horizontally,  just  below  the  tuberosities,  and  including  the 
articular  facet  for  the  fibula  and  depression  for  insertion  of 
semimembranosus  tendon,  while  in  front  it  dips  down  to 
include  the  tubercle.  The  head  of  the  tibia  is  practically 
divided  into  two  lateral  articular  surfaces  by  the  spine,  and 
extending  from  it  forwards  and  backwards  are  two  wedge- 
shaped  rough  areas,  which  give  attachment  respectively  to  the 
anterior  and  posterior  cornua  of  the  semilunar  cartilages  and 
the  crucial  ligaments.  The  upper  third  of  the  tibia  is  the 
part  of  the  bone  least  subject  to  fracture.  Either  tuberosity 
may  be  broken  off,  or  a  transverse  or  oblique  fracture  of  the 
upper  third  of  the  shaft  may  be  associated  with  a  vertical  one 
running  up  into  the  joint  between  the  tuberosities. 

The  epiphyseal  plates  of  the  long  bones  deserve  attention 
surgically  for  several  reasons.  They  are  ill-developed  in 
infancy,  become  very  marked  during  the  actively  growing 
period  up  to  seventeen  or  eighteen,  and  disappear  later.  They 
separate  the  shaft,  or  diaphysis,  from  the  extremity, or  epiphysis, 
and,  as  they  are  extremely  resistant  structures,  they  tend  to 
confine  the  various  affections  to  the  part  from  which  they 
originate.  Thus,  tubercle  and  giant-celled  sarcoma  generally 
affect  the  epiphyses,  and  particularly  those  now  under  con- 
sideration— the  lower  femoral  and  upper  tibial.  The  epi- 
physeal plates  form  resistant  barriers  to  these  diseases,  and 
are  frequently  successful  in  limiting  them  to  the  epiphyses. 
Acute  osteomyelitis,  on  the  other  hand,  is  a  pyogenic  invasion 
of  the  bone-marrow  of  the  shafts,  or  diaphyses,  of  long  bones, 


342  SURGICAL  ANATOMY 

the  infection  being  conveyed  by  the  blood-stream,  which  most 
frequently  affects  the  lower  end  of  the  femoral  shaft,  or  upper 
end  of  the  tibial  shaft.  The  pus  formed  seeks  an  exit,  and 
•tends  to  invade  the  knee-joint,  and  generally  succeeds  in 
doing  so  in  infancy  and  in  adults.  In  adolescence,  however, 
where  the  epiphyseal  plate  forms  a  barrier,  the  joint  is  pro- 
tected, and  the  pus  is  forced  to  seek  exit  between  the  end  of 
the  shaft  and  the  epiphysis,  or  through  the  Haversian  canals 
of  the  shaft,  causing  inflammation  of  the  bone,  or  osteitis,  as 
it  does  so.  Arrived  on  the  outer  surface  of  the  shaft  of  the 
bone,  it  lies  under  the  periosteum,  another  structure  of 
considerable  surgical  importance. 

The  periosteum  is  a  tough  fibrous  coat,  which  lines  the 
diaphyses  of  long  bones,  wrhich  acts  as  a  limiting  membrane 
to  the  bone  cells,  or  osteoblasts,  keeping  them  in  bounds,  and 
which  supplies  the  bone  with  blood,  particularly  in  youth  and 
adolescence,  in  addition  to  that  supplied  by  the  nutrient 
artery.  Between  the  periosteum  and  the  shaft  is  a  thin  layer 
of  loose  connective  tissue  in  which  numerous  osteoblasts 
generally  lie.  It  should  be  noted  that  the  periosteum  has  no 
power  of  forming  bone,  that  function  belonging  to  the  osteo- 
blasts. In  infancy  the  periosteum  is  practically  continuous 
with  the  synovial  membrane  of  the  joint,  while  in  adolescence 
the  periosteum  dips  in,  and  becomes  intimately  connected 
with  the  edges  of  the  epiphyseal  plates. 

To  revert,  then,  to  the  progress  of  the  pus  in  osteomyelitis. 
It  spreads  in  the  loose  areolar  tissue  between  periosteum  and 
shaft,  stripping  the  periosteum,  cutting  off  the  periosteal 
blood-supply,  and  frequently  killing  the  bone  in  mass — 
necrosis.  It  also  tends  to  invade  the  joint  from  this  position, 
and  is  generally  successful  in  infancy,  owing  to  the  connection 
between  periosteum  and  synovial  membrane ;  whereas  in 
adolescence  the  periosteum,  dipping  in  to  fuse  with  the  epi- 
physeal plate,  protects  the  joint  from  invasion.  Sooner  or 
later  the  periosteum  becomes  involved  in  the  pyogenic 
process — periostitis — is  softened  and  perforated,  and  the  pus 
forms  a  superficial  abscess,  which  bursts.  It  will  therefore  be 
seen  that  if  osteomyelitis  is  to  be  treated  successfully  it  must 
be  done  at  once,  an  exit  being  given  to  the  pus  while  it  is  yet 
in  the  medulla  of  the  bone,  and  before  it  has  done  much 
damage,  and  come  to  the  surface. 


LOWER  EXTREMITY  343 

The  knee-joint  is  supplied  with  blood  by  the  five  articular 
branches  of  the  popliteal  already  described,  and  derives  its 
nerve-supply  from  branches  of  the  nerves  to  the  vasti  (anterior 
crural)  in  front  ;  from  the  internal  and  external  popliteal 
(great  sciatic)  laterally  and  behind,  and  from  the  geniculate 
branch  of  the  obturator  posteriorly. 

Fluid  DISTENSION  of  the  knee-joint  frequently  occurs  as 
a  result  of  injury,  the  distension  in  tubercular  disease  being 
more  commonly  due  to  masses  of  granulation  tissue  within 
the  joint.  The  suprapatellar  pouch  becomes  markedly  dis- 
tended, while  the  patella  is  raised  from  the  trochlear  surface 
on  a  waterbed  (floating  patella).  As  in  the  case  of  the 
hip,  a  position  of  flexion  is  that  in  which  the  joint  accom- 
modates most  fluid,  and  hence  a  flexion  of  some  25 
degrees  is  generally  met  with  in  cases  of  distension  of  the 
joint  from  acute  or  chronic  affections,  that  being  the  position 
of  maximum  capacity.  The  muscles,  supplied  by  the  same 
nerves  as  the  joint,  aid  in  actively  keeping  the  joint  in  this 
position,  and  night  starlings — a  condition  characteristic  of 
joint  affections  where  ulceration  of  cartilage  has  occurred  to 
some  extent — are  due  to  the  relaxation  and  possibly  jerking 
of  these  muscles  on  sleep  supervening,  producing  a  jarring  of 
the  bones  on  one  another,  the  delicate  nerve  fibrils  which  exist 
in  such  abundance  just  under  the  articular  cartilage  being 
crushed.  As  articular  cartilage  does  not  contain  sensory  nerve 
filaments,  the  normal  joint  does  not  give  rise  to  acute  pain  on 
jarring,  unless  excessive.  The  flexed  position  if  persisted  in 
may  become  permanent,  due  to  contraction  of  the  muscles  and 
ligaments,  and  also  to  anchylosis  of  the  joint,  while  in  other 
cases,  where  the  joint,  including  the  crucial  and  other  liga- 
ments, is  disorganized  by  disease,  a  subluxation  is  liable  to 
occur,  the  head  of  the  tibia  being  drawn  backwards  by  the 
contracted  hamstring  muscles,  while  slight  eversion  is  also 
frequently  observed,  due  probably  to  the  action  of  the  biceps. 

Knock-knee,  being  an  affection  of  the  lower  third  of  the 
femur,  and  not  of  the  joint,  is  treated  under  that  heading. 

The  knee-joint  is  frequently  excised  for  tubercular  disease, 
generally  through  a  horseshoe  incision  from  one  condyle  to 
the  other,  above  the  patella,  the  skin,  fasciae,  quadriceps,  and 
synovial  membrane  being  cut  through,  and  the  joint  opened. 
The  diseased  synovial  tissue  is  removed,  the  lower  portion  of 


344  SURGICAL  ANATOMY 

the  condyles  of  the  femur  and  the  head  of  the  tibia  sawn  off, 
care  being  taken  with  regard  to  the  latter  not  to  remove  so 
thick  a  slice  as  to  imperil  the  epiphyseal  cartilage,  and  to  break 
rather  than  cut  the  last  small  portion  at  the  back  of  the  tibia, 
so  as  to  avoid  injury  to  the  vessels,  the  artery  lying  just 
behind  the  posterior  ligament.  Care  must  also  be  taken 
that  the  cuts  are  so  made  as  to  leave  the  limb  perfectly 
straight  when  the  cut  surfaces  are  accurately  in  apposition. 
Unlike  other  joints,  the  aim  in  excision  of  the  knee  is  to  secure 
broad  surfaces  on  both  bones,  so  as  to  obtain  firm  osseous 
anchylosis.  While  a  movable  joint  can  be  obtained  by 
excision  of  the  knee,  it  has  been  found  to  be  of  no  practical 
value,  and  generally  unfit  to  support  the  weight  of  the  body. 

DISLOCATIONS  of  the  knee-joint  are  rare,  are  generally  due 
to  great  and  often  direct  violence,  and,  as  a  rule,  the  joint  is 
opened,  the  lateral  and  crucial  ligaments  being  torn  when  the 
dislocation  is  complete.  The  tibia  may  be  displaced  in  any 
direction,  the  lateral  displacement  being  perhaps  more  common 
and  less  complete.  Of  the  antero-posterior  dislocations,  the 
forward  displacement  of  the  tibia  is  the  more  common,  and  in 
this  form  the  vessels  and  nerves  are  said  to  be  more  damaged 
by  the  femur  than  by  the  tibia  in  the  backward  form.  As  a 
matter  of  fact,  the  vessels  and  nerves  are  apt  to  be  damaged 
by  the  severe  injury  which  causes  the  dislocation,  and  as  a 
rule  the  damage  to  the  joint  is  such  that  the  tibia  may  be 
freely  moved  in  any  direction,  antero-posteriorly  or  laterally. 

AMPUTATION  at  the  knee-joint  may  be  performed  by  various 
methods.  In  Smith's  operation  two  lateral  flaps  are  made, 
commencing  below  the  tibial  tuberosity,  and  extending  down- 
wards for  fully  3  inches,  that  on  the  inner  side  being  made  the 
larger  to  accommodate  the  internal  condyle.  The  flaps  con- 
sist of  skin  and  cellular  tissue  alone,  and  the  condyles  of  the 
femur  are  not  cut,  a  disarticulation  being  performed.  Garden, 
Gritti,  Lister  and  also  use  skin-flaps,  but  they  remove  the 
condyles.  Garden  makes  an  anterior  horseshoe  from  one 
condyle  to  the  other,  crossing  the  centre  of  the  ligamentum 
patellae  below,  and  joins  the  ends  of  this  incision  by  a  posterior 
transverse  one.  Gritti  makes  the  same  incision,  but  extends 
it  to  the  lower  border  of  the  tibial  tuberosity,  and  he  retains  the 
patella  which  he  attaches,  after  cutting  off  the  cartilaginous 
surface  to  the  cut  surface  of  the  femur.  Lister  makes  an 


LOWER  EXTREMITY  345 

anterior  transverse  cut  at  the  level  of  the  tibial  tuberosity,  and 
joins  the  ends  of  the  anterior  by  a  posterior,  which  descends  at 
an  angfe  of  45  degrees  to  the  anterior. 

THE  LEG — SURFACE  ANATOMY. — The  tibial  crest  running 
in  a  curved  course  downwards  from  the  tibial  spine  forms  a 
prominent  landmark,  while  its  internal  surface  being  subcu- 
taneous is  easily  palpated  throughout  its  entire  length.  The 
fibula  is  situated  distinctly  behind  the  tibia  in  the  greater  part 
of  its  course,  and  its  head  is  easily  made  out,  lying  a  finger's 
breadth  below  the  knee,  with  the  biceps  tendon  inserted  into 
it,  and  the  external  popliteal  nerve  lying  to  the  inner  side  of 
the  biceps  tendon,  and  again  crossing  the  neck,  while  the  lower 
fourth  is  subcutaneous,  and  separates  the  peroneus  tertius  in 
front  from  the  peronei  longus  and  brevis  behind.  Two  lines, 
drawn  respectively  from  the  front  and  back  of  the  head  of  the 
fibula  to  the  anterior  and  posterior  borders  of  the  external 
malleolus,  give  the  positions  of  the  anterior  and  posterior 
peroneal  sulci,  along  which  intermuscular  septa  are  given  off 
from  the  deep  fascia,  which  pass  to  the  anterior  and  external 
borders  of  the  fibula.  Lying  between  the  tibial  crest  and  the 
anterior  peroneal  sulcus  are  the  extensor  muscles,  anterior 
tibial  vessels,  and  nerves.  Between  the  two  peroneal  sulci  lie 
the  two  principal  peroneal  muscles  and  the  musculo-cutaneous 
branch  of  the  external  popliteal  nerve,  whose  other  branch, 
the  anterior  tibial,  perforates  the  anterior  peroneal  septum 
and  extensor  longus  digitorum  muscle  to  reach  the  extensor 
compartment.  Between  the  posterior  peroneal  sulcus  and 
the  inner  border  of  the  tibia  lie  the  flexor  muscles  and  posterior 
tibial  vessels  and  nerve.  The  long  internal  and  short  external 
saphenous  veins  can  generally  be  made  out,  the  former,  accom- 
panied by  the  long .  saphenous  nerve,  running  from  the  front 
of  the  internal  malleolus  along  and  internal  to  the  inner  border 
of  the  tibia,  while  the  latter,  accompanied  by  the  external 
saphenous  nerve,  runs  from  behind  the  outer  malleolus  along 
the  middle  of  the  calf  to  the  popliteal  space.  The  association 
of  these  veins  with  nerves,  as  likewise  the  association  of  the 
deep  posterior  tibial  veins  with  the  posterior  tibial  nerves,  is 
given  as  a  reason  for  the  pain  which  so  frequently  accompanies 
varicose  veins.  In  this  connection  it  may  be  mentioned  that 
pain  referred  to  the  leg  may  arise  from  pressure  applied  to 
the  sciatic  trunk  or  obturator  intrapelvically.  Thus  carci- 


346  SURGICAL  ANATOMY 

noma  recti  may  cause  pain  referred  to  the -knee  and  leg.  Renal 
calculus  is  said  also  sometimes  to  cause  pain  referred  to  the 
foot.  The  tibial  vessels  are  given  off  at  the  level  of  the  lower 
margin  of  the  tubercle  of  the  tibia.  The  course  of  the  anterior 
tibial  is  indicated  by  a  line  from  a  point  midway  between  the 
external  tuberosity  of  the  tibia  and  head  of  the  fibula  to  the 
centre  of  the  front  of  the  ankle  ;  that  of  the  posterior  tibial  by 
a  line  from  the  centre  of  the  popliteal  space  to  a  point  midway 
between  the  inner  malleolus  and  the  prominence  of  the  heel. 
The  posterior  tibial  is  superficial  in  the  lower  fourth  of  the 
leg,  where  it  lies  between  the  tibia  and  the  tendo  Achillis  ;  it 
gives  off  the  peroneal  3  inches  below  the  knee,  which  vessel 
runs  along  the  posterior  surface  of  the  fibula  to  end  behind  the 
outer  malleolus. 

The  SKIN  of  the  leg  generally  is  more  adherent  than  that  of 
the  thigh,  and  this  is  particularly  the  case  over  the  superficial 
portions  of  the  shafts  of  the  tibia  and  fibula.  A  blow  on  the 
skin  is  apt  to  cut  the  integument  upon  the  sharp  edge  of  the 
tibial  crest,  and  injuries  and  ulcers  occurring  in  this  region 
may  readily  expose  or  even  involve  the  bone,  old  scars  fre- 
quently being  found  adherent  to  the  bone.  The  superficial 
veins  of  the  leg  lie  in  the  subcutaneous  tissue,  superficial  to  the 
deep  fascia,  while  the  deep  veins  accompany  the  arteries  under 
the  deep  fascia,  each  artery  distal  to  the  popliteal  having  a 
couple  of  venae  comites.  Both  groups,  but  particularly  the 
superficial,  are  frequently  affected  by  VARICOSITY,  owing 
probably  to  their  dependent  position  and  vertical  direction,  and 
the  consequently  long  column  of  blood -they  must  support  ; 
the  possibility  of  the  large  abdominal  trunks  which  they  ulti- 
mately enter  being  pressed  on ;  and  in  the  case  of  the  super- 
ficial veins  the  comparative  want  of  support  from  either 
deep  fascia,  or,  more  important,  muscular  contraction.  The 
wearing  of  garters,  compressing  the  veins  against  the  firm, 
deep  fascia,  may  also  influence  their  occurrence.  Normally 
the  circulation  in  the  veins  is  carried  on  by  the  vis  a  tergo  of  the 
heart,  the  suction  action  of  the  chest  in  inspiration,  and 
muscular  action,  the  intermittent  action  of  the  two  latter 
being  compensated  by  the  valves  in  the  interior  of  the  veins, 
which  prevent  any  backward  flow.  Varicosity  first  shows 
itself  at  these  valves,  frequently  in  situations  where  deep  and 
superficial  veins  communicate,  by  a  series  of  dilatations. 


LOWER  EXTREMITY  347 

Following  the  dilatation,  the  valves  become  incompetent, 
engorgement  follows,  and  the  vein  stretches  and  becomes 
tortuoufc,  while  the  surrounding  skin,  suffering  from  the 
defective  circulation,  frequently  becomes  pigmented,  and  is 
prone  to  ulceration.  In  some  cases  the  trunk  of  the  internal 
saphenous  (or  more  rarely  the  external  saphenous)  is  alone 
affected,  the  dilatation  extending  up  to  the  saphenous 
opening  ;  in  others  the  dilatation  is  general.  The  DEEP  FASCIA 
of  the  leg,  continuous  with  that  of  the  thigh,  invests  the  whole 
limb,  save  where  the  bones  are  subcutaneous,  where  it  is  inter- 
rupted and  attached  to  the  bony  margins  on  either  side  of  the 
subcutaneous  portion.  It  is  also  attached  to  the  head  of 
the  fibula.  It  is  thicker  in  front  than  behind,  particularly  just 
below  the  knee,  and  it  is  strengthened  below  at  the  annular 
ligaments.  Its  peroneal  septa  have  already  been  described. 

In  the  COMPARTMENT  between  the  tibial  crest  and  the 
anterior  septa  are  the  tibialis  anticus  and  extensor  communis 
digitorum,  extensor  longus  hallucis  and  peroneus  tertius 
muscles,  anterior  tibial  vessels  and  nerve,  and  anterior  branch 
of  the  peroneal  artery.  At  the  upper  end  of  the  compartment 
the  two  first-named  muscles  lie  together,  and  are  said  to  be 
separated  from  one  another  by  a  septum,  which  is  the  guide 
to  the  underlying  vessels.  As  a  matter  of  fact,  the  position  of 
the  septum  has  generally  to  be  guessed,  and  then  on  separating 
the  muscles  the  ANTERIOR  TIBIAL  ARTERY,  with  its  venae 
comites,  is  found  lying  on  the  interosseous  membrane. 
Toward  its  lower  extremity  the  compartment  narrows, 
and  the  relation  of  the  muscles  alters,  the  extensor  hallucis 
intervening  between  the  border  of  the  tibialis  anticus  and  the 
extensor  digitorum,  the  artery  therefore  below  the  middle  of 
the  leg  being  sought^on  the  interosseous  membrane  or  anterior 
surface  of  the  shaft  of  the  tibia  between  the  tibialis  anticus 
and  external  hallucis.  At  the  ankle  the  artery  is  crossed  by 
the  tendon  of  the  extensor  hallucis,  and  lies  superficially 
between  it  and  the  extensor  digitorum.  It  is  continuous  with 
the  dorsalis  pedis  of  the  foot.  Its  most  important  branch  is 
probably  the  anterior  tibial  recurrent  already  mentioned. 
After  ligature  of  the  anterior  tibial,  the  collateral  circulation  is 
kept  up  by  the  external  malleolar  of  the  anterior  tibial  with  the 
peroneals;  the  internal  malleolar  of  anterior  tibial  with  pos- 
terior tibial ;  and  the  dorsalis  pedis  and  plantar  with  peroneals. 


348  SURGICAL  ANATOMY 

The  peroneus  tertius,  arising  from  the  lower  third  of  the 
fibula  on  its  inner  aspect,  sends  its  tendon  down  on  the  outer 
side  of  that  of  the  extensor  digitorum.  The  branch  of  the 
peroneal  artery  enters  the  space  just  above  the  inferior  tibio- 
fibular  joint.  The  anterior  tibial  nerve  lies  external  to  the 
artery,  but  may  be  reached  through  the  same  incisions.  In 
the  upper  third  the  nerve  is  a  little  distance  from  the  artery , 
but  is  close  to  it  in  the  lower  two-thirds,  and  may  even  overlap 
it  in  the  middle  third. 

The  PERONEAL  COMPARTMENT  between  the  two  septa  con- 
tains the  peroneus  longus  and  brevis,  the  musculo-cutaneous 


13 


FIG.  41. — OUTLINE  DIAGRAM  OF  TRANSVERSE  SECTION  OF  LEG  IN  THE 
UPPER  THIRD. 

(Modified  from  Heath.) 

1.  Peroneus  long.  7.   Flex.  long,  pollicis. 

2.  Ext.  long.  dig.  9.   Gastrocnem.   (plantaris  tendon  above 

3.  Tibialis  anticus.  figure  on  right  side). 

Ant.  tibial  vessels  and  nerve  between         10.   Peroneal  vessels  on  left.     Post,  tibial 
3  and  4.  vessels  and  nerve  on  right. 

4.  Tibialis  posticus.  n.   Int.  saphenous  vein. 

5.  Flex.  long.  dig.  12.   Ext.  saphenous  vein  and  nerve. 
6  and  8.  Soleus.                                                      13.  Communicans  peror.ei  nerve. 

nerve,  and  at  its  upper  end  the  termination  of  the  external 
popliteal  nerve.  Both  peronei  muscles  arise  from  the  outer 
surface  of  the  fibula,  the  longus  from  the  upper  two-thirds,  and 
the  brevis  from  the  middle  two-fourths.  The  musculo- 
cutaneous  nerve  of  the  external  popliteal  lies  on  the  inner 
surface  of  the  peronei  which  it  supplies,  and  between  them 
and  the  extensor  digitorum. 

The  POSTERIOR  COMPARTMENT  between  the  external  peroneal 
septum  and  the  inner  border  of  the  tibia  is  wide  above,  but 


LOWER  EXTREMITY  349 

diminishes  as  it  approaches  the  ankle.  It  contains  a  super- 
ficial group  of  muscles,  the  gastrocnemius,  soleus,  and 
plantarte,  which  are  separated  from  the  deep  group,  consisting 
of  the  flexor  longus  digitorum,  flexor  longus  hallucis,  and 
tibialis  posticus  by  an  intermuscular  septum  running  from  the 
fibula  to  the  tibia.  The  posterior  tibial  vessels  and  nerve, 
and  the  peroneal  vessels,  lie  in  the  deep  compartment,  super- 
ficial to  the  deep  muscles.  The  gastrocnemius  rapidly  narrows, 
and  becomes  tendinous  about  the  middle  of  the  leg,  the  soleus 
remaining  fleshy  to  a  lower  level.  The  tendons  of  the  two 
muscles  coalesce  to  form  the  TENDO  ACHILLIS,  which  is  in- 
serted into  the  posterior  part  of  the  os  calcis,  and  is  an 
important  landmark.  The  long  thin  tendon  of  the  plantaris 
runs  down  from  without  inwards  between  these  two  muscles, 
and  is  inserted  into  the  os  calcis  on  the  inner  side  of  the  tendo 
Achillis. 

The  tendo  Achillis  is  not  infrequently  ruptured  by  some 
unwonted  exertion,  and  the  plantaris  tendon  has  been  simi- 
larly injured,  while  the  gastrocnemius  muscle  has  also  been 
partially  torn. 

The  POSTERIOR  TIBIAL  ARTERY,  accompanied  by  its  venae 
comites,  lies  between  the  superficial  and  deep  muscles  on  the 
under  surface  of  the  deep  intermuscular  septum,  just  over  the 
tibialis  posticus.  The  posterior  tibial  nerve  lies  at  first  to  the 
inside  of  the  artery,  but  about  ij  inches  below  the  popliteus 
muscle  it  crosses  behind  the  artery  to  the  outer  side.  The 
vessel  is  deeply  placed  in  its  upper  two-thirds,  and  is  best 
reached  about  the  middle  of  the  leg,  through  an  incision  on  a 
line  from  the  inner  tuberosity  of  the  tibia  to  a  point  midway 
between  the  internal  malleolus  and  the  heel,  the  patient  lying 
on  the  back,  with  the  limb  everted.  The  skin  and  superficial 
fascia  are  incised,  avoiding  the  internal  saphenous  vein  and 
nerve  ;  then  the  deep  fascia  is  cut  through,  and  the  gastro- 
cnemius drawn  backwards  and  the  soleus  exposed.  The  soleus 
is  now  divided  vertically  in  the  line  of  the  incision,  until  the 
vessel  is  reached  lying  under  the  deep  fascia.  This  portion  of  the 
operation  is  difficult,  the  incision  being  apt  to  follow  the  fibres 
of  the  soleus,  instead  of  going  vertically  through  them,  while 
a  tendinous  intersection  in  the  substance  of  the  soleus  is  apt 
to  be  mistaken  for  the  deep  aponeurosis.  The  tibial  margin 
forms  a  good  guide,  the  incision  being  deepened  at  a  uniform 


350  .  SURGICAL  ANATOMY 

distance  from  it  (less  than  a  finger's  breadth),  until  the  vessel 
is  reached.  In  the  lower  one-third  the  vessel  is  comparatively 
superficial,  and  lies  midway  between  the  inner  margin  of  the 
tibia  and  the  tendo  Achillis.  To  reach  it,  an  incision  in  the  line 
of  the  artery  is  made  through  the  skin,  superficial  fascia, 
deep  fascia,  and  deep  fascia  covering  the  deep  flexors.  The 
artery  lies  on  the  flexor  longus  digitorum. 

The  collateral  circulation  is  by  calcaneal  branches  of  external 
plantar  with  the  peroneals  and  external  malleolar  of  anterior 
tibial,  plantar  arteries  with  dorsalis  pedis,  internal  malleolar 
of  anterior  tibial  with  posterior  tibial,  and  muscular  branches 
of  peroneal  and  posterior  tibial. 

Aneurism  of  the  posterior  tibial  is  said  to  be  more  apt  to 
cause  gangrene  of  the  leg  than  popliteal  aneurism,  as  it 
presses  upon  the  anterior  tibial  recurrent,  which  plays  an 
important  part  in  collateral  circulation. 

In  the  upper  portion  of  the  leg  the  deep  posterior  muscles 
are  arranged  with  the  tibialis  posticus  placed  centrally,  spring- 
ing from  the  interosseous  membrane  and  tibia  and  fibula, 
while  the  flexor  hallucis,  springing  from  the  fibula,  lies  to  the 
outer  side,  and  the  flexor  digitorum,  springing  from  the  tibia, 
lies  to  the  inner  side.  Near  the  ankle  the  tendon  of  the 
tibialis  posticus  passes  under  that  of  the  flexor  digitorum,  and 
is  thus  above,  or  anterior  to,  the  others.  Next  to  it  comes  the 
flexor  digitorum  tendon,  then  the  artery  and  its  venae  comites, 
then  the  nerve,  and  finally  the  flexor  hallucis  lies  lowest,  or 
most  posterior. 

The  peroneal  artery,  arising  about  i  inch  below  the  end  of 
the  popliteal,  inclines  out  to  the  posterior  surface  of  the 
fibula,  and  descends  in  or  beneath  the  flexor  longus  hallucis, 
close  to  the  interosseous  membrane.  Just  above  the  ankle  it 
divides  into  anterior  and  posterior  peroneal  arteries,  of  which 
the  anterior  enters  the  anterior  compartment,  through  the 
interosseous  membrane,  to  anastomose  with  branches  of  the 
anterior  tibial,  and  the  posterior  descends  posteriorly  to  anasto- 
mose with  the  anterior  malleolar  and  tarsal  vessels.  The 
peroneal  also  supplies  muscular  branches,  and  the  nutrient 
artery  to  the  fibula.  While  all  the  vessels  of  the  lower  limb 
are  apt  to  be  injured  in  fracture,  the  peroneal  is  particularly 
so,  owing  to  its  close  relationship  to  the  fibula  and  its  com- 
parative fixation. 


LOWER  EXTREMITY  351 

BONES  OF  THE  LEG.— It  should  be  remembered  that  the 
tibia  alone  articulates  with  the  femur,  and  therefore  bears  the 
whole  Weight  of  the  body,  while  the  fibula  supplements  it,  par- 
ticularly in  resisting  lateral  and  torsion  forces,  and  assists  in 
forming  the  ankle-joint  by  the  external  malleolus.  The  tibia 
is  thickest  in  front,  in  the  region  of  the  crest,  and  about  the 
centre  of  the  bone.  The  narrowest  part  is  at  the  junction  of 
the  middle  and  lower  thirds,  measuring  about  i  inch  in  trans- 
verse diameter,  while  the  average  diameter  is  if  inches,  and 
farther,  at  this  point,  internally,  two  columns  of  spongy 
matter,  one  occupying  the  upper  two-thirds,  and  the  other 
the  lower  one-third,  meet,  and  thus  this  point  is  the  weakest, 
and  it  is  here  that  fractures  of  the  tibia  from  indirect  violence 
generally  occur. 

FRACTURE  of  the  tibia  alone  is  generally  due  to  direct 
violence,  affects  the  lower  one-third  most  frequently,  and 
when  transverse  often  presents  no  displacement,  the  fibula 
acting  as  a  splint,  and  occasionally  enabling  the  patient  to 
walk. 

The  nutrient  foramen  of  the  tibia  is  the  largest  in  the  body, 
and  enters  the  posterior  surface  of  the  bone  in  its  upper  third, 
whence  it  is  directed  downwards  in  the  compact  shaft  for 
about  2  inches  before  entering  the  medulla.  The  shaft  of 
the  tibia  is  very  frequently  affected  by  acute  osteomyelitis, 
which,  if  it  succeeds  in  plugging  the  nutrient  artery,  in 
addition  to  stripping  the  periosteum,  may  cause  death  of  the 
shaft  from  cutting  off  the  blood-supply.  In  operating  on  the 
tibia  for  osteomyelitis  the  disease  is  easily  attacked  through 
the  superficial  broad  internal  aspect.  The  shaft  of  the  tibia 
is  also  a  frequent  seat  of  syphilitic  nodes,  a  chronic  periostitis 
being  set  up,  which  results  in  the  formation  of  a  char- 
acteristic spindle  -  shaped  osseous  node.  In  some  cases 
gummatous  changes  take  place,  the  skin  breaks  down,  and 
deep  ulcers  form,  wThile  the  bone  may  become  softened  and 
bend. 

Rickets  attacks  the  tibia  and  also  the  fibula  at  an  early  stage, 
various  deformities  being  produced.  Perhaps  the  most 
common  is  a  curve,  with  the  convexity  directed  forwards,  and 
inwards  or  outwards,  occurring  about  the  junction  of  middle 
and  lower  third,  the  malleolus  touching  the  ground  in  severe 
cases.  A  general  curving  of  the  tibia,  with  the  convexity 


352  SURGICAL  ANATOMY 

outwards,  occurs  frequently  in  genu  varum,  and  almost  the 
whole  deformity  in  some  of  these  cases  lies  in  the  tibia,  and 
not  in  the  femur.  A  cuneiform  osteotomy  is  generally  per- 
formed to  rectify  the  more  acute  tibial  curves,  a  wedge  being 
removed  from  the  convexity  of  the  curve.  The  lower  epi- 
physis  of  the  tibia,  which  includes  the  malleolus  and  the 
fibular  facet,  may  be  separated  by  injury.  It  unites  with  the 
shaft  about  the  eighteenth  year.  The  malleolus  may  be  broken 
by  violence,  and  its  tip  is  frequently  torn  off  in  Pott's  fracture 
of  the  fibula. 

The  shaft  of  the  fibula  is  narrow,  but  strong,  compact,  and 
somewhat  elastic,  presenting  several  sharp  projecting  ridges, 
which  act  as  flanges,  and  give  the  bone  in  section  a  shape  not 
altogether  unlike  that  of  a  girder.  As  in  addition  the  bone  is 
covered  by  muscles,  it  is  not  often  broken  alone,  despite  its 
exposed  position,  save  in  its  lower  one-fourth.  The  fracture 
which  occurs  in  that  position  is  due  to  indirect  violence,  is 
called  Pott's  fracture,  and  is  one  of  the  most  frequent  and 
important  fractures  in  the  body.  As  it  is  associated  with 
dislocation  of  the  ankle,  it  will  be  considered  under  that 
region.  Other  fractures  of  the  fibula  alone  are  generally  due 
to  direct  violence,  are  transverse,  and,  the  tibia  acting  as  a 
splint,  produce  little  or  no  displacement.  Where  both  bones 
are  broken  by  indirect  violence,  the  tibia  breaks  about  the 
junction  of  the  middle  and  lower  one-third,  the  line  of  fracture 
running  obliquely  downwards,  forwards,  and  inwards,  while 
the  fibula  breaks  higher  up.  This  fracture  is  very  apt  to 
become  compound,  not  only  because  the  crest  of  the  tibia  is 
sharp  and  very  superficial,  but  because  both  the  lower  end  of 
the  upper  fragment  tends  to  project  forwards,  and  also  the 
upper  end  of  the  lower  fragment,  being  tilted  by  the  tendo 
Achillis  pulling  the  heel  backwards  and  upwards.  The  weight 
of  the  foot  also  assists  in  producing  this  displacement  of  the 
lower  fragment,  and  in  addition  it  generally  produces  slight 
eversion.  The  superficial  position  of  the  tibia  also  favours 
comminution  in  fractures  by  direct  violence. 

A  SPIRAL  FRACTURE  of  the  tibia,  due  to  torsion,  sometimes 
occurs  at  the  junction  of  the  middle  and  lower  third,  running 
obliquely  down  and  inwards,  the  upper  fragment  presenting 
a  V-shaped  extremity  (Gosselin),  while  in  some  cases  there  is 
in  addition  a  vertical  fracture,  extending  down  through  the 


LOWER  EXTREMITY  353 

lower  fragment  to  the  ankle,  and  the  fibula  may  break  at  a 
higher  level. 

AMPUTATION  of  the  leg  used  to  be  performed  at  a  point  a 
hand's  breadth  beneath  the  knee-joint  (seat  of  election),  the 
stump  left  by  this  operation  being  short,  and  enabling  the 
patient  to  walk  by  kneeling  on  a  pin-leg.  Nowadays,  speaking 
generally,  the  stump  should  be  left  as  long  as  possible,  the 
forms  of  amputation  used  being  adapted  to  circumstances. 
Amputation  at  the  seat  of  election,  or  middle  third,  may  be 
performed  by  long  anterior  and  short  posterior  flaps,  or  by  a 
single  large  external  flap,  which  may  be  made  to  contain  the 
anterior  tibial  artery  (Farabceuf).  Amputation  in  the  middle 
or  lower  third  may  be  done  by  a  large  posterior  flap ;  and 
Teale's  amputation,  in  which  a  long  anterior  flap,  four  times 
the  length  of  the  posterior,  is  taken,  and  then  turned  over  on 
itself,  so  that  the  scar  is  quite  away  from  the  apex  of  the  stump, 
may  be  performed  in  the  lower  third.  It  is  generally  well  to 
bevel  the  cut  end  of  the  tibia  so  as  to  remove  the  sharp  tip  of 
the  crest,  and  in  amputations  at  the  upper  extremity  cf  the 
leg  some  recommend  the  removal  of  the  upper  end  of  the 
fibula.  Owing  to  the  fibula  lying  behind  the  plane  of  the 
tibia,  it  is  sometimes  possible  in  amputating  to  run  the  knife 
from  within  outwards  behind  the  tibia,  but  between  it  and 
the  fibula,  and  so  get  it  jammed. 

THE  ANKLE  AND  FOOT— SURFACE  ANATOMY.— The 
malleoli  form  prominent  landmarks,  the  tip  of  the  external 
malleolus  being  about  J  inch  below  and  behind  that  of  the 
internal,  while,  owing  to  the  greater  breadth  of  the  latter, 
their  posterior  borders  are  on  a  level  with  one  another.  In 
front  of  the  external  malleolus  and  external  to  the  tendon  of 
the  peroneus  tertius,  -and  between  the  internal  malleolus  and 
tendon  of  the  tibialis  anticus,  are  shallow  depressions,  which 
denote  the  position  of  the  ankle-joint.  These  depressions  are 
replaced  by  swellings,  when  the  joint  becomes  distended.  The 
joint  line  lies  about  J  inch  above  the  tip  of  the  internal 
malleolus.  Less  than  i  inch  below  and  in  front  of  the  external 
malleolus  lies  the  peroneal  spine  of  the  os  calcis,  with  the 
peroneus  brevis  above  and  the  peroneus  longus  below  it,  while 
less  than  i  inch  below  the  internal  malleolus  is  the  sustenta- 
culum  tali  of  the  os  calcis,  into  which  the  recurrent  slip  of  the 
tibialis  posticus  is  inserted,  while  the  flexor  longus  digitorum 

23 


354  SURGICAL  ANATOMY 

and  flexor  longus  hallucis  occupy  the  underlying  groove. 
The  tubercle  of  the  scaphoid,  which  receives  the  chief  insertion 
of  the  tibialis  posticus,  lies  about  I  inch  in  front  of  the 
internal  malleolus ;  and  over  2  inches  in  front  of  the  external 
malleolus  is  the  projecting  base  of  the  fifth  metatarsal,  with 
the  cuboid  behind  it.  The  mid-tarsal  joint,  that  between 
calcaneum  and  cuboid  and  between  the  astragalus  and 
scaphoid,  lies  internally  just  behind  the  tubercle  of  the 
scaphoid,  and  externally  just  in  front  of  the  midpoint  between 
the  external  malleolus  and  the  base  of  the  fifth  metatarsal. 
When  the  foot  is  extended,  the  astragalus  forms  a  prominence 
most  marked  in  front  of  the  external  malleolus,  and  below,  in 
front,  and  a  little  to  the  outside  of  this  prominence  is  a  de- 
pression, which  lodges  the  outer  end  of  the  astragalo-calcaneal 
ligament,  and  still  farther  in  front  is  a  slight  prominence,  due 
to  the  anterior  tuberosity  of  the  os  calcis,  which  articulates 
with  the  cuboid  in  front  The  tendons  lying  in  front  of  the 
ankle  are  best  seen  when  the  foot  is  extended,  and  consist  from 
within  outwards  of  tibialis  anticus,  extensor  longus  hallucis, 
extensor  longus  digitorum,  and  peroneus  tertius,  while  on  the 
outer  aspect  of  the  dorsum  the  belly  of  the  extensor  brevis 
digitorum  can  be  felt. 

The  sole  of  the  foot  presents  a  triangular  outline,  and  only  a 
comparatively  small  portion  of  it  comes  normally  in  contact 
with  the  ground.  The  parts  which  touch  the  ground  are  the 
heel,  external  border  of  the  foot,  and  ball  of  the  great  toe. 
The  foot  is  arched  antero-posteriorly,  arid  also  transversely. 

The  antero-posterior  arch  is  formed  by  bony  pillars — os  calcis 
and  astragalus  posteriorly,  and  the  anterior  tarsus  and  meta- 
tarsus anteriorly — and  is  maintained  by  the  plantar  fascia, 
the  plantar  and  inferior  calcaneo-scaphoid  ligaments,  .and 
tendons  of  the  peronei,  tibiales,  flexores  longus  digitorum 
and  hallucis. 

The  transverse  arch  is  formed  by  the  wedge  shape  of  the 
middle  and  external  cuneiform  bones,  and  second,  third,  and 
fourth  metatarsals,  and  is  supported  by  the  peroneus  longus 
tendon  and  short  ligaments  of  the  part.  In  the  front  of  the 
foot  the  whole  of  the  first  metatarsal  and  its  sesamoid  bones 
can  be  fairly  made  out.  It  articulates  behind  with  the 
internal  cuneiform.  The  metatarso-phalangeal  articulations 
are  about  i  inch  behind  the  webs  of  the  toes.  Posteriorly 


LOWER  EXTREMITY  355 

the  tendo  Achillis  forms  a  prominent  landmark.  The 
depression  to  its  outer  side  lodges  the  tendons  of  the  peronei 
longus  and  brevis,  the  latter  lying  anteriorly  and  more  deeply, 
in  contact  with  the  fibula,  while  that  on  its  inner  side  is  con- 
tinuous with  the  groove  under  the  sustentaculum  tali,  in 
which  are  lodged  the  tibialis  posticus  (next  the  tibia),  then 
the  flexor  longus  hallucis,  the  posterior  tibial  artery  and  venae 
comites,  posterior  tibial  nerve  and  flexor  longus  pollicis.  As 
these  latter  tendons,  with  the  vessels  and  nerve,  lie  well  in 
front  of  the  tendo  Achillis,  they  run  little  risk  of  being  wounded 
in  a  tenotomy  of  the  latter.  A  bursa  separates  the  lower 
portion  of  the  tendo  Achillis  from  the  os  calcis,  and  when 
inflamed  this  bursa  may  cause  swelling  and  pain  suggestive  of 
an  affection  of  the  ankle-joint,  and  may  even  lead  to  disease  of 
the  os  calcis.  Tenotomy  of  the  tendo  Achillis  is  performed 
by  introducing  a  blunt-pointed  tenotome  between  the  skin  and 
the  tendon  through  a  puncture  made  in  the  skin,  while  the 
foot  is  kept  extended  so  as  to  relax  the  tendon.  Then  the 
edge  of  the  tenotome  having  been  turned  against  the  tendon, 
the  foot  is  forcibly  flexed,  thereby  rendering  the  tendon  tense, 
and  dividing  it  against  the  blade,  a  considerable  gap  existing 
subsequently. 

The  dorsalis  pedis  artery  runs  from  the  middle  of  the  ankle- 
joint  to  the  space  between  the  bases  of  the  first  two  meta- 
tarsals  lying  to  the  outer  side  of  the  extensor  longus  hallucis 
tendon.  Starting  from  a  point  midway  between  the  tip  of 
the  internal  malleolus  and  the  heel,  the  plantar  arteries  run — 
the  internal  to  the  middle  of  the  under  surface  of  the  great  toe, 
the  external  to  a  point  about  i  inch  from  the  base  of  the  fifth 
metatarsal,  whence  it  turns  inwards. 

The  SKIN  over  the  ankle  and  dorsum  of  the  foot  is  thin  and 
freely  movable,  and  is  readily  damaged  from  pressure  on  the 
subjacent  parts.  On  the  sole  of  the  foot  the  parts  which  come 
in  contact  with  the  ground  are  thick  and  fairly  adherent  to 
the  dense  subcutaneous  tissue,  while  the  remainder  of  the 
skin  of  the  sole  is  thin,  smooth,  and  sensitive,  and  well  supplied 
with  sweat-glands.  In  some  respects  the  skin '  and  subcu- 
taneous tissue  of  the  sole  resembles  that  of  the  palm  ;  it  does 
not  tend  to  retract  when  cut ;  and  foreign  bodies,  such  as 
broken  needles,  when  embedded  in  it,  are  frequently  difficult 
to  find,  while  abscesses  remain  localized,  and  cause  much  pain. 

23—2 


356 


SURGICAL  ANATOMY 


The  SUBCUTANEOUS  TISSUE  is  lax  over  the  ankle  and  dorsum, 
and  is  frequently  the  part  first  affected  in  dropsy ;  is  abundant 
and  fatty  around  the  tendo  Achillis,  and  thick,  dense,  and 
fibrous  over  the  heel  (where  it  may  be  f  inch  thick),  and  over 
the  parts  which  come  in  contact  with  the  ground.  This  thick 
pad  forms  an  excellent  cushion,  and,  combined  with  the 
elasticity  of  the  arches  of  the  foot,  prevents  jarring  in  walking. 

The  superficial  veins  are  most  numerous  on  the  dorsum, 
where  they  form  a  plexus,  particularly  about  the  internal 


10 


FIG.  42.  — OUTLINE  DIAGRAM  OF  LONGITUDINAL  SECTION  OF  FOOT. 
(After  Braune.) 


i    Os  calcis. 

2.  Tibia. 

3.  Astragalus. 

4.  Scaphoid. 

5.  Int.  cuneiform. 

6.  First  metatarsal. 


7.  Flex,  accessorius. 

8.  Flex.  brev.  dig. 

9.  Flex,  conimun.  dig. 

10.  Adduct.  min.  dig. 

11.  Flex.  long,  hallucis. 

12.  Accessorius. 


13.  Flex.  brev.  hallucis. 

14.  Ext.  long,  hallucis. 

15.  Tendo  Achillis. 

16.  Post,  tibial  vessels  and  nerve. 

17.  Ext.  plantar  vessels  and  nerve. 

1 8.  Tibial.  antic. 


malleolus,  while  the  parts  of  the  sole  which  touch  the  ground 
are  comparatively  free  from  them.  Over  the  instep  there  are 
numerous  veins,  which  frequently  dilate  in  varicosity  of  the 
limb.  On  the  dorsum  the  veins  form  an  arch,  from  the 
extremities  of  which  the  saphenous  veins  arise. 

The  lymphatics  of  the  foot  form  a  fine  plexus,  the  chief 
vessels  being  situated  on  the  dorsum,  and  particularly  on  the 
inner  side,  whence  they  ascend  near  the  internal  saphenous 
vein  to  the  inguinal  lymphatic  glands.  A  few  of  the  external 
lymphatics  follow  the  short  saphenous  vein  to  the  popliteal 


LOWER  EXTREMITY  357 

glands,  but  the  majority  cross  the  leg,  particularly  behind  and 
above  the  knee,  to  join  the  inner  set,  a  few  crossing  in  front 
over  ttffe  tibia.  Thus,  septic  wounds  of  the  inner  side  of  the 
foot  will  probably  affect  the  inguinal  glands,  while  those  of 
the  outer  side  may  affect  either  the  popliteal  or  inguinal  set. 
The  skin  of  the  foot  derives  sensation  from  branches  of  the  an- 
terior tibial,  two  saphenous,  external  and  internal  plantar  and 
musculo-cutaneous  nerves.  Pacinian  bodies  and  end  bulbs 
are  found  on  their  terminations,  and  while  tactile  sensation  is 
not  acute,  the  sensations  of  pain,  pressure,  and  temperature 
are,  and  tickling  is  particularly  sharply  felt.  The  skin  of  the 
dorsum,  however,  is  much  less  sensitive  than  that  of  the  sole. 
Reference  has  already  been  made  to  pain  referred  to  the  foot 
from  bowel  and  other  distant  affections.  Perforating  ulcer  of 
the  foot  is  believed  to  be  due  to  a  neurosis,  is  frequently  met 
with  in  locomotor  ataxy,  rarely  in  diabetes,  and  generally 
affects  the  ball  of  the  great  toe,  and  less  frequently  the  heel. 
On  the  dorsum  the  FASCIA  is  divided  into  superficial  and 
deep  layers,  both  of  which  are  poorly  developed,  and  of 
little  importance.  The  superficial  layer  is  continuous  with 
the  anterior  annular  ligament,  and  the  deep  layer  covers  in 
the  extensor  brevis  and  interossei.  The  PLANTAR  FASCIA,  on 
the  other  hand,  consists  of  a  strong  central  portion,  running 
forward  from  the  tuberosity  of  the  os  calcis,  to  divide  into  five 
slips  to  the  bases  of  the  toes,  and  two  lateral  portions,  which 
are  much  less  well  developed,  and  join  the  dorsal  fascia.  The 
portion  on  the  outer  side  forms  a  stout  band,  the  calcaneo- 
metatarsal  ligament  between  the  tuberosity  of  the  os  calcis  and 
the  base  ol  the  fifth  metatarsal.  An  intermuscular  septum 
passes  up  on  either  side  of  the  flexor  brevis  digitorum,  separat- 
ing it  from  the  abductors  of  the  great  and  little  toes.  The 
plantar  fascia  helps  to  support  the  arch  of  the  foot,  and  in 
talipes  cavus,  where  the  foot  is  greatly  arched,  the  central  band 
may  be  strongly  contracted,  necessitating  section  before  the 
condition  can  be  remedied.  Such  section  is  best  performed 
about  i  inch  in  front  of  the  attachment  to  the  os  calcis,  where 
the  fascia  is  narrowed,  the  scalpel  being  introduced  from  the 
inner  side.  The  density  of  the  plantar  fascia  tends  to  prevent 
the  pointing  of  deep  abscesses  in  the  sole,  although  occasionally 
such  an  abscess  may  present  through  a  small  aperture  in  the 
fascia  normally  occupied  by  fat,  and  then  spread  subcu- 


358  SURGICAL  ANATOMY 

taneously  and  point.  Generally  such  abscesses  become  large, 
cause  considerable  destruction  of  tissue  and  pain,  and  finally 
point  on  the  dorsum  or  about  the  ankle.  At  the  ankle  the 
deep  fascia  is  strengthened,  and  forms  the  ANNULAR  LIGAMENTS 
— anterior,  internal,  and  external.  The  anterior  is  in  two 
portions — an  upper  running  between  the  malleoli,  which  binds 
down  the  tendons  of  the  tibialis  anticus  and  extensors  of  the 
toes,  the  former  surrounded  by  a  synovial  sheath,  and  a  lower 
attached  externally  to  the  os  calcis,  and  then  extending 
inwards  across  the  dorsum  and  splitting  into  two  portions,  the 
upper  inserted  into  the  internal  malleolus,  and  the  lower  to 
the  plantar  fascia.  Under  this  lower  portion  are  three  synovial 
sheaths — an  inner  for  the  tibialis  anticus,  a  middle  for  the 
extensor  proprius  hallucis,  and  an  outer  for  the  extensor 
communis  and  peroneus  tertius.  The  internal  annular  liga- 
ment extends  from  the  internal  malleolus  to  the  tuberosity  of 
the  os  calcis.  Under  it  pass  the  tibialis  posticus,  flexor  longus 
digitorum,  and  flexor  longus  hallucis  (each  enclosed  in  a 
separate  synovial  sheath,  that  for  the  tibialis  posticus  being 
closely  related  to  the  joint),  together  with  the  posterior  tibial 
vessels  and  nerve.  The  external  ligament  stretches  from  the 
external  malleolus  to  the  os  calcis.  Under  it  pass  the  peronei 
longus  and  brevis  in  a  single  synovial  sheath.  In  addition  to 
partial  rupture  of  the  ligaments,  sprains  of  the  ankle  are 
frequently  associated  with  damage  to  the  synovial  sheaths, 
causing  long-standing  trouble. 

Rupture  of  the  tendo  Achillis  has  already  been  referred  to. 
The  tendons  of  the  tibialis  posticus,  and  long  and  short  peronei, 
may  also  be  ruptured  by  violence,  and  in  some  cases  their 
sheaths  may  also  be  torn,  allowing  of  displacement  of  the 
tendons,  which  may  appear  in  front  of  the  malleoli.  The 
peroneus  longus  tendon  is  said  to  be  more  frequently  displaced 
than  any  other  in  the  body.  The  tibialis  anticus  tendon  may 
be  tenotomized  below  and  in  front  of  the  ankle,  as  it  crosses  the 
scaphoid  bone,  the  tenotome  being  introduced  beneath  it  from 
without  inwards.  The  tibialis  posticus  may  be  similarly 
treated,  either  just  above  the  internal  malleolus,  where  it  is 
subcutaneous,  or  between  the  internal  malleolus  and  tuberosity 
of  the  scaphoid.  As  these  tendons  run  in  sheaths,  their  section 
is  generally  undesirable,  the  cut  ends  tending  to  adhere  to  the 
synovial  sheath,  and  movement  thereby  being  much  im- 


LOWER  EXTREMITY 


359 


paired.     Their  section  in  cases  of  talipes  equino-varus  is  gener- 
ally not  only  useless,  but  harmful. 

The  interior  tibial  artery  is  crossed  at  the  ankle  by  the 
tendon  of   the  extensor  hallucis,   and  then  lies  between   it 


4... 


-- 1 


Cs? 


FIG.  43. — THE  SYNOVIAL  SHEATHS  AT  THE  ANKLE.     ANTERIOR  VIEW. 
(After  L.  Testut's  "  Anatomie  Humaine.") 


1.  Tibialis  anticus. 

2.  Extensor  proprius  hallucis. 


3.  Extensor  longus  digitorum. 

4.  Peroneus  longus  et  brevis. 


and  that  of  the  extensor  digitorum,  being  continued  into 
the  foot  as  the  DORSALIS  PEDIS.  This  vessel  lies  in  a  line 
from  the  centre  of  the  front  of  the  ankle  to  the  posterior 


360  SURGICAL  ANATOMY 

extremity  of  the  first  interosseous  space,  being  accom- 
panied on  its  outer  side  by  the  anterior  tibial  nerve  and 
lying  between  the  extensor  longus  hallucis  on  its  inner  side, 
and  the  innermost  tendon  of  the  extensor  digitorum  on  its 
outer  side.  The  vessel,  lying  as  it  does  superficially  and  close 
to  the  bones  of  the  foot,  is  frequently  divided  and  ruptured  in 
wounds  and  injuries,  and  its  ligature  presents  little  difficulty, 
save  in  the  cadaver,  where  a  slightly  more  superficial  vein  is 
frequently  mistaken  for  the  artery. 

The  POSTERIOR  TIBIAL  ARTERY  may  be  ligatured  at  the 
ankle  through  a  curved  incision  a  finger's  breadth  below  the 


FIG.  44. — THE  SYNOVIAL  SHEATHS  AT  THE  ANKLE.     INTERNAL  VIEW. 
(After  L.  Testut's  "Anatomic  Humaine. ") 


1.  Tibialis  posticus. 

2.  Flexor  longus  digitorum. 

3.  Flexor  longus  hallucis. 


4.  Extensor  proprius  hallucis 

5.  Tibialis  antit  us. 


internal  malleolus.  At  the  lower  border  of  the  internal  annular 
ligament  it  divides  into  internal  and  external  plantar  arteries, 
and  sends  calcaneal  branches  to  the  heel.  (The  anterior  and 
posterior  branches  of  the  peroneal  artery  descend  to  the  ankle, 
and  anastomose  with  the  branches  of  the  anterior  and  posterior 
tibials.)  The  internal  plantar  artery,  the  smaller  of  the  two, 
runs  forward  between  the  abductor  hallucis  and  flexor  brevis 
digitorum  to  the  head  of  the  first  metatarsal  bone,  while  the 
external  plantar  runs  forwards  and  outwards  between  the 
flexor  brevis  digitorum  and  abductor  minimi  digiti  to  the 


LOWER  EXTREMITY  361 

base  of  the  fifth  metatarsal,  where  it  turns  abruptly  inwards 
to  form  the  plantar  arch,  which  crosses  the  bases  of  the  meta- 
tarsafs  to  the  outer  side  of  the  base  of  the  first  metatarsal 
to  anastomose  with  the  dorsalis  pedis.  The  course  of  the 
internal  plantar  is  represented  by  a  line  from  a  point  midway 
between  the  internal  malleolus  and  prominence  of  the  heel  to 
the  middle  of  the  under  surface  of  the  great  toe ;  the  external 
runs  from  the  same  point  to  within  J  inch  of  the  base  of  the 
fifth  metatarsal.  Wounds  of  the  plantar  arch  are  troublesome, 
not  only  because  it  lies  deeply  and  might  necessitate  damage 
to  tendons  and  nerves  to  reach  it,  but  because  of  the  free 
anastomoses  between  the  anterior  and  posterior  tibial  and 
peroneal  arteries.  It  has  been  suggested  to  reach  the  vessel 
from  the  dorsum  by  removal  of  portions  of  one  or  more  meta- 
tarsal bones,  but  haemorrhage  can  often  be  arrested  by  pressure 
on  the  inner  vessels,  with  firm  local  pressure  and  elevation  of 
the  limb. 

THE  ANKLE-JOINT.— The  lower  ends  of  the  tibia  and 
fibula  are  firmly  bound  together  by  a  series  of  ligaments,  while 
the  malleoli  project  beyond  and  form  a  socket  into  which  the 
upper  and  external  surfaces  of  the  astragalus  fit. 

The  LIGAMENTS  which  hold  the  bones  together  are  anterior 
and  posterior  inferior  tibio-fibular  ligaments  ;  an  interosseous 
ligament,  which  is  continuous  above  with  the  interosseous 
membrane,  and  below  comes  into  association  with  the  joint 
cavity  ;  and  a  transverse  ligament,  which  stretches  posteriorly 
from  the  internal  malleolus  to  the  inner  aspect  of  the  posterior 
border  of  the  external  malleolus.  Sometimes  there  is  an 
actual  joint  between  the  two  bones,  lined  with  articular  carti- 
lage, and  the  synovial  membrane  of  the  ankle-joint  extends  up 
between  the  bones.-  The  ligaments  of  the  ankle-joint  form  a 
continuous  investment  of  very  varying  strength.  The 
anterior  ligament  is  a  weak  structure,  attached  above  to  the 
lower  border  of  the  tibia  and  to  the  malleoli,  and  below  to  the 
neck  of  the  astragalus ;  and  the  posterior  ligament,  also  weak, 
extends  from  the  posterior  surface  of  the  tibia  to  the  astra- 
galus, and  is  strengthened  by  the  transverse  ligament  already 
described.  Effusions  of  fluid  into  the  ankle-joint  generally 
show  first  in  front,  beneath  the  extensor  tendons,  owing  to  the 
weakness  of  the  anterior  ligament  and  looseness  of  the  synovial 
membrane  at  that  point,  and  if  increased  cause  bulgings  of  the 


362  SURGICAL  ANATOMY 

posterior  ligament,  which  show  as  fulness,  with  fluctuation  on 
either  side  in  front  of  the  tendo  Achillis.  The  lateral  ligaments 
are  very  powerful,  particularly  the  internal,  which  is  triangular 
in  shape,  the  apex  being  attached  above  to  the  internal 
malleolus,  and  the  base  to  the  scaphoid  in  front,  then  the 
inferior  calcaneo-scaphoid  ligament  and  neck  of  the  astragalus, 
and  behind  to  the  sustentaculum  tali  and  inner  surface  of  the 
astragalus.  It  is  covered  by  the  tendons  of  the  tibialis 
posticus  and  flexor  longus  digitorum.  The  external  lateral 
ligament  consists  of  three  fasciculi  all  arising  from  the  external 
malleolus,  of  which  the  anterior  extends  to  the  astragalus,  the 
middle  to  the  os  calcis  (being  covered  by  the  tendons  of  the 
peronei),  and  the  posterior  to  the  posterior  aspect  of  the 
astragalus,  being  attached  to  a  small  tubercle  of  bone,  which  is 
occasionally  distinct  from  the  astragalus  (os  trigonum) . 

The  SYNOVIAL  MEMBRANE  lines  the  capsule,  is  lax  anteriorly 
and  posteriorly,  where  it  covers  pads  of  fat,  and  is  directly 
continuous  with  the  inferior  tibio-fibular  joint,  when  it  exists. 
The  joint  is  supplied  by  branches  of  the  anterior  tibial  and 
internal  saphenous  nerves,  the  former  associating  it  with  the 
sacral  segments  of  the  cord,  and  the  latter  with  the  lumbar. 
The  ankle-joint  only  permits  of  flexion  and  extension,  save  in 
extreme  extension,  when  very  slight  lateral  movement  is  just 
possible,  owing  to  the  narrow  posterior  portion  of  the  astra- 
galus coming  in  contact  with  the  wider  anterior  portion  of  the 
tibio-fibular  cavity.  Flexion  is  limited  by  the  posterior 
ligament  and  posterior  portions  of  the  lateral  ligaments,  and 
by  contact  of  the  astragalus  with  the  tibia.  Extension  is 
limited  by  the  anterior  ligament  and  anterior  portions  of  the 
lateral  ligaments,  and  by  contact  of  the  astragalus  with  the 
tibia.  Lateral  movements  of  the  foot  round  an  antero- 
posterior  axis  take  place  normally  between  the  astragalus  and 
the  os  calcis,  while  those  round  a  vertical  axis  take  place  at 
the  midtarsal  joint.  The  position  of  greatest  ease  of  the  joint 
is  that  of  slight  extension,  although  the  capacity  is  not  affected 
by  position. 

SPRAINS  of  the  ankle  frequently  occur,  a  forced  movement 
of  the  foot  producing  partial  tearing  of  one  or  other  lateral 
ligament.  Sometimes  the  ligaments  withstand  the  strain,  and 
a  portion  of  one  of  the  malleoli  is  torn  off  by  it,  the  condition 
being  called  a  sprain  fracture. 


LOWER  EXTREMITY  363 

DISLOCATIONS  of  the  ankle  are  generally  associated  with 
fracture,  and  are  due  to  indirect  violence  applied  to  the  foot. 
Sometimes,  as  a  result  of  injury,  one  of  the  malleoli  may  alone 
be  broken,  no  dislocation  resulting.  The  ankle  may  be  dislo- 
cated laterally,  antero-posteriorly,  or  upwards.  The  outward 
lateral  displacement  is  by  far  the  most  common,  and  is  associ- 
ated with  a  fracture  of  the  fibula  some  2  or  3  inches  from  its 
lower  end,  the  condition  being  known  as  Pott's  fracture. 
Pott's  fracture  is  caused  by  a  violent  eversion  of  the  foot, 
such  as  is  produced  by  stepping  sidewise  from  a  machine  in 
motion,  the  internal  lateral  ligament  tearing  and  the  astragalus 
being  rotated,  and  so  brought  violently  against  the  external 
malleolus.  As  the  ligaments  binding  the  fibula  to  the  tibia, 
remain  intact,  this  portion  acts  as  a  fulcrum,  and,  the  malleolus 
being  forcibly  everted,  the  lower  end  of  the  shaft  of  the  fibula 
is  forcibly  inverted,  and  finally  snaps  some  3  inches  up. 
Frequently  the  tip  of  the  internal  malleolus  is  torn  off  instead 
of  the  internal  lateral  ligament  giving  way.  After  the  injury 
the  foot  is  displaced  markedly  outwards  and  everted,  and 
there  is  also  a  tendency  to  backward  drooping  of  the  heel  when 
the  patient  is  recumbent.  Dupuytren's  fracture  is  a  somewhat 
similar  condition,  which,  however,  is  rare,  and  only  produced 
by  extreme  violence.  In  it,  while  the  fracture  of  the  fibula 
remains  the  same,  the  tibio-fibular  articulation  gives  way,  and 
the  everted  astragalus  is  forced  up  between  the  two  bones,  or 
the  lower  fragment  of  the  fibula  accompanies  the  astragalus 
upwards.  A  simple  dislocation  of  the  astragalus  upwards 
between  the  tibia  and  fibula  without  fracture,  but  with  lacera- 
tion of  the  tibio-fibular  ligaments,  rarely  occurs,  generally  from 
a  fall  on  the  feet.  Complete  inward  dislocation  of  the  ankle 
is  rare,  is  generally  caused  by  a  severe  twist,  and  is  said  to  be 
accompanied  by  fracture  of  the  external  malleolus,  and  often 
of  the  internal  malleolus,  and  even  of  the  astragalus.  Com- 
plete inward  dislocation  has  occurred,  however,  without 
fracture  of  any  part.  Antero-posterior  dislocations  of  the 
astragalus  are  less  common,  and  are  caused  by  violence  with 
the  foot  fixed  as  in  jumping  from  a  moving  vehicle  in  the  line 
of  its  motion.  Of  the  two  forms,  backward  dislocation  of  the 
astragalus  is  much  the  more  common,  the  articular  surface  of 
the  tibia  resting  on  the  scaphoid  and  cuneiform  bones,  and 
all  the  ligaments  suffering,  particularly  the  anterior  and 


364  SURGICAL  ANATOMY 

posterior.     Here  also  the  fibula  may  be  fractured,  and  one 
or  both  malleoli  may  be  detached. 

The  Tarsus. — THREE  SETS  OF  JOINTS  exist  in  the  tarsus  : 
(i)  Between  astragalus  and  os  calcis  (posterior).  (2)  (a)  Be- 
tween astragalus  and  scaphoid,  (b)  between  os  calcis  and 
cuboid.  These  two  together  constitute  the  midtarsal  joint. 
(3)  (a)  Between  scaphoid  and  three  cuneiforms,  (b)  between 
the  cuneiforms,  (c)  between  external  cuneiform  and  cuboid. 

1.  This  consists  of  two  parts,  entirely  separated  by  the 
strong   astragalo-calcaneal   ligament   which   unites   the   two 
bones.     The    anterior  portion   is  continuous   with  the  joint 
between  the  head  of  the  astragalus  and  the  scaphoid.  Compara- 
tively weak  peripheral  ligaments  (external,  internal,  and  pos- 
terior) also  help  to  unite  the  two  bones,  which  are  further 
strengthened  by  the  lateral  ligaments  of  the  ankle  and  various 
tendons.     The  articulation  permits  of  adduction  with  slight 
rotation  inwards,  and  abduction  with  slight  rotation  outwards. 

2.  (a)  This  articulation  is  continuous  with  the  last,  and  is 
of  the  ball  and  socket  variety.     The  lower  aspect  of  the  head 
of  the  astragalus  is  supported  by  the  inferior  calcaneo-scaphoid 
ligament,  which  is  a  powerful  band  of  triangular  shape,  running 
from   the   sustentaculum   tali   to   the   under   surface   of   the 
scaphoid,  and  which  again  is  supported  on  its  under  surface 
by  the   tendon  of   the  tibialis  posticus.      There  is  also   an 
external  calcaneo-scaphoid  and  an  astragalo-scaphoid  ligament, 
the  latter  situated  on  the  upper,  or  dorsal,  surface  of  the 
articulation,     (b)    Each    bone    presents    a    concavo-convex 
surface  mutually  adapted  to  one  another.     The  joint  is  sup- 
ported by  an  internal  calcaneo-cuboid  ligament,  which  springs 
from   the    os     calcis,    together    with    an   external    calcaneo- 
scaphoid  ligament,  the  two  diverging  in  the  form  of  the  letter  V, 
to   be  inserted  into   the  scaphoid  and   cuboid  respectively. 
There  are  also  external  and  dorsal  calcaneo-cuboid  ligaments, 
while  below  are  situated  the  inferior  calcaneo-cuboid,  or  plantar, 
ligaments.     The  short  plantar  ligament  is  more  deeply  placed, 
and  extends  from  the  anterior  tubercle  on  the  inferior  surface 
of  the  os  calcis  to  the  proximal  part  of  the  under  surface  of 
the  cuboid.     The  long  plantar  ligament  covers  the  short,  and 
is  separated  from  it  by  some  fatty  tissue.     It  extends  from  the 
posterior  tuberosities  of  the  os  calcis  along  its  whole  inferior 
surface   to   the  ridge   on   the  under  surface   of   the  cuboid, 


LOWER  EXTREMITY  365 

immediately  behind  the  peroneal  groove,  some  fibres  being 
continued  over  the  groove  to  the  bases  of  the  second,  third, 
and  fourth  metatarsals.  The  long  plantar  is  a  powerful  liga- 
ment, and  together  with  the  short  plantar  and  inferior  cal- 
caneo-scaphoid  ligaments  plays  an  important  part  in  main- 
taining the  arch  of  the  foot.  The  midtarsal  joint  permits  of 
flexion  and  extension  and  rotation  on  an  antero-posterior  axis, 
the  movement  in  the  astragaloid  section  being  freer  than  that 
in  the  calcaneal. 

3.  These  joints  are  supplied  with  dorsal,  interosseous,  and 
strong  plantar  ligaments,  the  latter  being  reinforced  by  slips 
from  the  tibialis  posticus  tendon. 


FIG.  45. — DIAGRAM  OF  THE  Six  SYNOVIAL  MEMBRANES  OF  THE  FOOT. 

1.  Os  calcis.  5.   Internal  cuneiform. 

2.  Astragalus.  6.   Middle  cuneiform. 

3.  Scaphoid.  7.  External  cuneiform. 

4.  Cuboid.  8.  Interosseous  ligament. 

THE  TARSO-METATARSAL  ARTICULATIONS. — The  first  meta- 
tarsal  articulates  with  the  internal  cuneiform  by  a  complete 
joint,  which  undergoes  an  outward  subluxation  in  the  con- 
dition called  hallux  valgus,  the  suppurating  bunion,  which 
frequently  forms  in  this  condition,  sometimes  communicating 
with  and  causing  disorganization  of  the  joint.  The  second 
and  third  metatarsal  bones  articulate  with  the  middle  and 
-external  cuneiform  bones  respectively,  being  connected  by 
dorsal  and  plantar  ligaments,  the  latter  reinforced  by  slips 
from  the  tibialis  posticus  tendon.  The  second  metatarsal, 
however,  is  connected  to  both  internal  (ligament  of  Lisfranc) 
and  external  cuneiforms  by  means  of  interosseous  ligaments. 
The  fourth  'and  fifth  metatarsals  articulate  with  the  cuboid, 


366  SURGICAL  ANATOMY 

being  connected  by  dorsal  and  plantar  ligaments,  the  latter 
reinforced  by  slips  from  the  long  plantar  ligament.  The  fourth 
also  is  connected  to  the  external  cuneiform  by  an  interosseous 
ligament,  and  the  bases  of  the  third  and  fourth  are  also  con- 
nected by  an  interosseous  ligament.  There  are  six  SEPARATE 
JOINT  CAVITIES  in  the  tarsus  and  metatarsus — namely, 
(i)  Posterior  calcaneo-astragaloid.  (2)  Calcaneo-astragalo- 
scaphoid.  (3)  Calcaneo-cuboid.  (4)  Anterior  tarsal.  This  is 
a  large  articulation,  and  extends  (a)  between  the  scaphoid  and 
three  cuneiforms  ;  (b)  between  each  of  the  cuneiforms,  and 
between  the  external  cuneiform  and  cuboid  ;  (c)  between  the 
bases  of  the  second  and  third  metatarsals,  and  middle  and 
external  cuneiforms  respectively  ;  (d)  between  the  contiguous 
surfaces  of  the  second,  third,  and  fourth  metatarsals. 
(5)  Between  internal  cuneiform  and  first  metatarsal.  (6)  Be- 
tween cuboid  and  fourth  and  fifth  metatarsals. 

The  bones  of  the  foot  are  frequently  affected  by  tubercular 
disease,  the  os  calcis  being  most  frequently  affected,  then  the 
base  of  the  first  metatarsal,  astragalus,  cuboid,  etc.  The 
disease  generally  affects  the  neighbouring  joints,  and  in  the 
case  of  the  scaphoid  the  large  anterior  tarsal  joint  may  be 
involved,  and  the  disease  thus  become  widely  diffused.  The 
tendon  sheaths  also  become  affected  at  times,  especially  the 
tibial  and  peroneal.  In  operating  it  is  important  to  preserve, 
where  possible,  the  os  calcis,  which  supports  the  heel,  and  the 
head  of  the  first  metatarsal,  which  supports  the  ball  of  the  toe. 
The  os  CALCIS  is  frequently  affected  by  tubercular  cario- 
necrosis,  in  which  a  spherical  portion  of  bone  is  killed  in  mass 
(necrosis)  by  a  spreading  ulceration  (caries),  which  surrounds 
and  cuts  it  off.  Such  disease  can  frequently  be  removed 
without  excision  of  the  bone.  The  os  calcis,  while  frequently 
fractured,  is  seldom  dislocated,  and  when  displaced  is  generally 
displaced  outwards.  It  is  the  most  frequently  fractured  tarsal 
bone,  the  fracture  occurring  from  falls  on  the  heel  or  from 
muscular  action,  the  tendo  Achillis  tearing  off  the  posterior 
portion.  Ossification  begins  in  the  sixth  month  of  fcetation.  ' 

The  ASTRAGALUS  may  be  dislocated  forwards,  backwards,  or 
laterally,  the  latter  being  generally  associated  with  forward 
movement.  Forward  dislocation  is  the  most  common,  is 
generally  complete,  frequently  compound,  and  is  generally 
associated  with  fracture  of  the  tibia,  fibula,  or  astragalus  itself. 


LOWER  EXTREMITY  367 

In  all  cases  the  malleoli  come  nearer  the  sole,  and  there  is  also 
inversion  in  the  forwards  and  outwards  variety,  and  eversion 
in  the  forwards  and  inwards  variety.  Siibastragaloid  disloca- 
tion of  the  foot  occurs  through  the  astragalo-scaphoid  and 
astragalo-calcaneal  joints,  the  astragalus  retaining  its  position, 
and  the  foot  being  displaced  generally  backwards,  and  either 
in  or  outwards.  In  the  former  the  foot  is  inverted  and  curved 
with  the  convexity  on  the  outer  side,  thus  resembling  talipes 
varus  ;  in  the  latter  the  foot  is  everted,  and  the  head  of  the 
astragalus  forms  a  projection  on  the  inner  aspect.  The  con- 
dition is  frequently  compound,  and  is  generally  incomplete  as 
regards  the  astragalo-calcaneal  joint,  and  complete  in  the 
astragalo-scaphoid  joint.  The  astragalo-calcaneal  ligaments 
are  torn,  and  the  malleoli  are  frequently  fractured.  Fracture 
of  the  astragalus  may  result  from  a  fall  on  the  feet,  and  is 
frequently  associated  with  fracture  of  the  os  calcis,  but 
fracture  of  the  bones  of  the  leg  is  a  more  usual  consequence. 
Ossification  begins  in  the  astragalus  in  the  seventh  month  of 
foetal  life.  Dislocations  of  the  SCAPHOID,  CUNEIFORMS,  and 
individual  METATARSALS  have  been  reported,  but  none  of  the 
cuboid  alone.  The  cuboid  begins  to  ossify  at  birth,  and  the 
scaphoid  in  the  third  year.  Dislocations  of  all  the  metatarsals 
occur  rarely,  that  upwards  being  the  most  common. 

Deformities  of  the  foot  are  generally  classed  under  the 
heading  of  talipes,  of  which  there  are  four  principal  varieties  : 
talipes  varus,  talipes  valgus,  talipes  equinus,  and  talipes 
calcaneus.  The  most  common  form  of  talipes  is  a  combination 
of  two  of  these — namely,  talipes  equino-varus — the  foot  being 
turned  inwards,  so  that  the  patient  walks  on  the  outer  side 
(talipes  varus),  while  the  heel  and  posterior  portion  of  the  foot 
are  drawn  up,  so  -that  the  patient  walks  on  the  anterior 
portion  of  the  foot  only  (talipes  equinus).  In  addition  the 
foot  as  a  whole  is  somewhat  curled,  the  sole  becoming  concave, 
and  the  toes  being  frequently  so  much  turned  inwards  that 
in  running  the  child  requires  to  lift  one  foot  over  the  other. 
This  form  is  generally  congenital,  being  due  to  a  want  of  foetal 
unwinding,  and  consists  primarily  of  a  deformity  of  the  bones, 
the  astragalus  being  principally  affected,  the  muscles  and 
ligaments  being  sometimes  affected  secondarily.  The  neck  of 
the  astragalus  is  lengthened  and  curved,  so  that  the  head, 
which  articulates  with  the  scaphoid,  looks  inwards  instead  of 


368  SURGICAL  ANATOMY 

forwards,  as  it  normally  does,  and  while  the  body  of  the  bone 
is  roughly  cubical  normally,  it  becomes  wedge-shaped  in 
talipes,  the  base  of  the  wedge  being  directed  to  the  outside 
of  the  foot,  and  the  apex  to  the  inside.  The  scaphoid  and  the 
os  calcis  may  also  become  somewhat  wedge-shaped,  and  the 
former  may  be  so  turned  round  that  its  tubercle  touches  the 
internal  malleolus,  while  the  latter  is  placed  almost  vertically. 
The  weight  of  the  body  rests  therefore,  not  on  the  heel,  but  on 
the  cuboid  and  external  surface  in  front  of  it,  the  prominence 
of  the  cuboid  on  the  outer  side  of  the  foot  being  generally 
accentuated  by  the  presence  of  a  bursa.  At  birth  and  for 
some  time  afterwards  the  condition  can  generally  be  rectified 
by  manipulation  alone,  the  bones  being  cartilaginous  and  soft, 
and  tending  to  unwind.  Later,  they  become  hard  and  un- 
yielding, and  other  changes  occur,  the  muscles  attached  to  the 
tendo  Achillis  becoming  atrophied  and  contracted,  the  tibiales 
possibly  becoming  similarly  affected,  while  the  plantar  fascia 
also  becomes  contracted,  and  the  knees  tend  to  become  slightly 
hyperextended  and  stiff.  In  such  cases  excision  of  the  astra- 
galus, combined  if  necessary  with  tenotomy  of  the  tendo 
Achillis,  yields  good  results. 

Pure  TALIPES  VARUS  is  very  uncommon.  TALIPES  VALGUS 
is  the  opposite  of  talipes  varus,  the  foot  being  everted  and 
raised,  so  that  the  patient  walks  on  the  inner  margin.  A  pure 
valgus  is  not  often  met  with,  the  condition  being  generally 
associated  with  flat-foot,  which  is  sometimes  meant  when  the 
term  talipes  valgus  is  used.  In  the  usual  type  of  valgus  the 
foot  is  flat,  the  arch  being  lost,  and  the  head  of  the  astragalus 
and  the  scaphoid  presenting  in  the  sole.  TALIPES  EQUINUS 
and  TALIPES  CALCANEUS  generally  are  acquired,  being  due  to 
atrophy  and  contraction  of  the  muscles  of  the  leg,  often  secon- 
darily to  poliomyelitis.  In  the  former  the  heel  is  raised  from 
the  ground  by  contraction  of  the  muscles  attached  to  the  tendo 
Achillis,  and  the  patient  walks  on  the  balls  of  the  toes,  the 
foot  frequently  becoming  curved  from  the  transmission  of 
weight  and  contraction  of  the  plantar  fascia,  so  that  heel  and 
toes  approach  one  another  (talipes  cavus).  In  the  latter, 
which  is  less  common,  the  anterior  part  of  the  foot  is  drawn 
up,  and  the  patient  walks  on  the  heel,  which  is  generally  very 
prominent,  owing  to  the  tilting  of  the  os  calcis  with  projection 
of  its  posterior  end. 


LOWER  EXTREMITY  '369 

Flat-foot  is  due  to  a  loss  of  tone  and  stretching  of  the  tendons 
and  ligaments  of  the  sole  of  the  foot.  In  consequence  the 
greater^.portion  of  the  sole  of  the  foot  comes  in  contact  with 
the  ground,  the  foot  tending  also  to  become  slightly  abducted. 
In  bad  cases  the  osseous  arch  may  sink  to  such  an  extent  that 
the  head  of  the  astragalus  and  the  tubercle  of  the  scaphoid  may 
present  in  the  sole.  The  affection  is  generally  painful,  the 
pain  being  frequently  referred  to  the  region  of  the  ankle,  and 
is  best  treated  by  attention  to  the  tone  of  the  muscles  and 
ligaments,  walking  on  the  balls  of  the  toes,  etc.  In  severe 
cases  a  wedge  has  been  removed  from  the  tarsal  bones 
(tarsectomy),  and  the  patient  thus  given  a  fixed  osseous  arch. 

The  TOES  are  subject  to  various  deformities,  especially  the 
great  and  second  toes.  Hallux  valgus  has  already  been  men- 
tioned. Hallux  rigidus  consists  of  a  fixed  flexion  of  the  meta- 
tarso-phalangeal  joint.  Hammer  toe  is  a  condition  which 
most  frequently  affects  the  second  toe,  that  toe  being  the 
longest  in  a  classical  foot,  and  so  being  pressed  upon  by  badly- 
fitting  boots,  or  by  the  great  toe  in  hallux  valgus.  It  becomes 
dorsiflexed  at  the  metatarso-phalangeal  joint,  flexed  at  the 
first  interphalangeal  joint,  and  hyperextended  at  the  last 
interphalangeal  joint.  A  corn  frequently  develops  over  the 
first  interphalangeal  joint,  and  another  over  the  tip  of  the  toe, 
and  considerable  pain  is  caused.  The  tendons  and  ligaments 
become  contracted  in  the  later  stages. 

AMPUTATION  OF  THE  FOOT  may  be  performed  through  the 
tarso-metatarsal  joint  (Lisfranc),  or  through  the  midtarsal 
joint  (Chopart),  or  at  the  ankle  (Syme).  The  latter  generally 
yields  the  most  serviceable  stump.  In  Lisfranc's  amputation 
a  plantar  flap  is  raised  by  an  incision  across  the  bases  of  the 
toes,  and  extending  backwards  to  the  bases  of  the  first  and 
fifth  metatarsal  bones,  all  the  structures  down  to  the  bones 
being  included — namely,  skin,  subcutaneous  tissue,  abductor 
minimum  digiti,  flexor  brevis  hallucis  and  minimi  digiti, 
transversus  pedis,  and  tendons  of  the  flexor  longus  digitorum 
and  hallucis,  tibialis  posticus  tendinous^expansions,  plantar 
vessels  and  nerves.  The  dorsal  flap  has  a  convexity  forwards, 
and  runs  from  the  base  of  the  first  to  that  of  the  fifth  meta- 
tarsal, and  also  includes  the  structures  down  to  the  bone — 
namely,  skin,  fascia  with  superficial  veins  and  musculo- 
cutaneous  nerve,  tendons  of  the  extensor  communis  and  brevis 

24 


3?o  SURGICAL  ANATOMY 

digitorum,  extensor  longus  hallucis,  tibialis  anticus,  and 
anterior  tibial  nerve  and  dorsalis  pedis  artery.  The  articula- 
tion between  the  base  of  the  first  metatarsal  and  the  internal 
cuneiform  is  then  opened,  care  being  taken  not  to  go  too  far 
back  and  open  the  joint  between  the  internal  cuneiform  and 
scaphoid  instead.  Then  the  three  outer  metatarsals  are  dis- 
articulated from  the  tarsus.  The  chief  difficulty  lies  in  dis- 
articulating the  second  metatarsal,  the  base  of  which,  articu- 
lating with  the  short  middle  cuneiform,  is  mortized  in  between 
the  internal  and  external  cuneiforms.  The  position  of  the 
articulation  is  sought  on  the  dorsal  surface  with  the  point  of 
the  knife,  the  metatarsal  being  strongly  flexed,  and  once  the 
basal  joint  is  opened  the  lateral  articulations  with  internal 
and  external  cuneiforms  are  divided,  that  with  the  internal 
cuneiform  presenting  the  strong  ligament  of  Lisfranc.  The 
whole  of  the  metatarsals  are  now  removed,  the  tendons  of  the 
tibialis  posticus  (expansions)  and  peroneus  longus  on  the 
plantar,  and  peronei  brevis  and  tertius  on  the  dorsal  aspect, 
being  cut.  The  internal  cuneiform  forms  a  marked  projection, 
and  is  difficult  to  cover  unless  a  very  abundant  flap  has  been 
provided.  Hey,  instead  of  disarticulating  the  first  metatarsal, 
saws  through  the  internal  cuneiform  at  the  level  of  the  articu- 
lation between  middle  cuneiform  and  second  metatarsal, 
while  Skey  saws  across  the  base  cf  the  second  metatarsal 
instead  of  disarticulating,  and  Cooper  saws  across  the  bases  of 
all  the  metatarsals,  the  tendons  of  the  peronei  and  tibialis 
anticus  being  thus  left  intact,  and  the  large  anterior  synovial 
cavity  unopened.  Chopart's  amputation  is  performed  by 
making  a  short  dorsal  flap  from  behind  the  tubercle  of  the 
scaphoid  to  a  finger's  breadth  behind  the  base  of  the  fifth 
metatarsal,  reaching  anteriorly  to  the  bases  of  the  meta- 
tarsals ;  and  a  plantar  flap,  which,  commencing  and  ending  at 
the  same  points,  extends  forwards  to  the  centre  of  the  meta- 
tarsals, both  flaps  taking  all  structures  down  to  the  bone,  and 
are  as  given  for  Lisfranc,  save  that  the  peroneus  brevis 
and  peroneus  tertius  are  cut  in  the  dorsal,  and  flexor  acces- 
sorius  and  tibialis  posticus  are  cut  in  the  plantar  flaps.  Dis- 
articulation  is  done  from  within  outwards  through  the 
astragalo-scaphoid  and  calcaneo-cuboid  joints. 

Syme's  amputation  is  performed  by  taking  a  point  just  below 
and  in  front  of  the  external  malleolus,  and  a  point  opposite 


LOWER  EXTREMITY  371 

to  it  on  the  inside.  These  points  are  joined  by  a  vertical 
incision  made  with  the  foot  strongly  dorsiflexed,  so  as  to  keep 
behincKthe  ridge  of  the  posterior  tuberosity  of  the  os  calcis. 
The  flap  is  cut  down  to  the  bone,  and  is  then  dissected  up, 
care  being  taken  to  keep  close  to  the  bone,  and  so  avoid  injury 
to  the  vessels.  The  tendo  Achillis  may  be  cut  close  to  its 
origin  or  peeled  off.  The  ends  of  the  first  incision  are  now 
joined  across  the  dorsum,  the  foot  is  firmly  extended,  and 
disarticulated  at  the  ankle.  The  malleoli  are  then  sawn  off, 
and  the  wound  closed.  The  anterior  tibial  artery  is  cut  in 
the  centre  of  the  anterior  incision,  the  nerve  lying  to  its  outer 
side,  and  the  long  saphenous  vein  to  its  inner  side.  The  small 
anterior  peroneal  artery  is  also  cut  on  the  front  of  the  ankle. 
The  peroneus  tertius,  extensor  hallucis,  and  tibialis  anticus 
muscles  are  cut  in  front.  The  plantar  arteries  and  nerves  are 
cut  on  the  inner  side  of  the  heel  flap,  and  the  external 
saphenous  vein  and  nerve  on  the  outer.  The  peronei  longus 
and  brevis,  abductor  hallucis,  tibialis  posticus,  flexors  longus 
hallucis,  and  digitorum  are  divided  in  the  heel  flap.  In 
Pirogoff's  amputation  the  posterior  portion  of  the  os  calcis  is 
cut  off  instead  of  being  removed,  and  is  attached  to  the  cut 
surface  of  the  tibia. 


The  Nerves  of  the  Lower  Extremity. 

The  SPINAL  ORIGINS  of  the  nerves  supplying  the  muscles  of 
the  lower  limb  are  : — adductors,  ilio-psoas,  pectineus,  sartorius 
(third  lumbar)  ;  quadriceps  extensor  cruris  (fourth  lumbar)  ; 
hamstrings,  glutei  medius  and  minimus,  tensor  fasciae  femoris 
(fifth  lumbar)  ;  gluteus  maximus,  short  external  rotators  of 
hip-joint,  peronei,  extensors  of  toes,  flexors  of  ankle  (first 
sacral)  ;  gastrocnemius,  soleus,  long  flexors  of  toes,  extensors 
of  ankle,  muscles  of  sole  (second  sacral) . 

The  OBTURATOR  NERVE  arises  from  the  second  to  the  fourth 
lumbar  nerves  in  the  psoas  muscle,  from  the  inner  border  of 
which  it  emerges  to  pass  through  the  obturator  foramen  into 
the  thigh,  dividing  into  superficial  and  deep  branches,  of  which 
the  former  supplies  the  hip-joint  through  the  cotyloid  notch, 
the  adductors  longus,  gracilis,  and  brevis,  the  femoral  artery 
in  Hunter's  canal,  and  the  skin  over  the  lower  two-thirds  of 
the  inside  of  the  thigh.  The  deep  branch  supplies  the 

24 — 2 


372  SURGICAL  ANATOMY 

obturator  externus  muscle,  the  adductors  magnus  and  bn>vis, 
and  the  knee-joint. 

Injury  of  this  nerve  alone  is  rare,  but  may  be  caused  by 
pressure  of  the  foetal  head  or  of  an  obturator  hernia.  In 
paralysis,  adduction,  or  crossing,  of  the  limbs  is  impossible,  and 
outward  rotation  difficult.  Sensation  is  also  affected  over  the 
part  of  the  thigh  supplied. 

The  ANTERIOR  CRURAL  nerve  arises  from  the  second  to  the 
fourth  lumbar  nerves  in  the  psoas  muscle,  from  which  it 
emerges  on  the  outer  border,  to  enter  the  thigh  between  the 
psoas  and  iliacus  muscles,  which  it  supplies  by  passing  under 
Poupart's  ligament.  In  the  thigh  it  supplies  the  pectineus, 
sartorius,  and  quadriceps,  articular  branches  to  the  hip  and 
knee  joints,  and  middle  and  internal  cutaneous  branches  to 
supply  the  greater  portion  of  the  front  of  the  thigh.  The  long, 
or  internal  saphenous,  branch  accompanies  the  femoral  vessels 
to  the  inner  side  of  the  knee,  where  it  supplies  an  articular 
branch  to  the  knee-joint,  and  a  branch  to  the  patellar  plexus, 
and  then  supplies  the  skin  of  the  leg  and  foot  in  front,  and 
to  the  inner  side. 

The  nerve  may  be  injured  by  fractures,  or  tumours,  of  the 
pelvis,  psoas  abscess,  etc.,  and  when  paralyzed  the  hip  cannot 
be  flexed  (ilio-psoas) ,  nor  the  knee  extended  (quadriceps). 

The  GREAT  SCIATIC  nerve  arises  from  the  fourth  and  fifth 
lumbar,  and  the  first  to  the  third  sacral  nerves,  passes  out 
through  the  great  sciatic  foramen,  and  divides  into  internal  (or 
tibial)  and  external  (or  peroneal)  popliteal  nerves.  The  trunk 
supplies  articular  branches  to  the  hip  and  knee  joints,  muscular 
branches  to  the  hamstrings  and  smaller  muscles  of  the  hip. 
The  tibial  nerve  is  derived  from  the  anterior  trunks  of  the 
fourth  and  fifth  lumbar,  and  first  and  second,  and  part  of  the 
third  sacral,  while  the  peroneal  is  derived  from  the  posterior 
trunks  of  the  fourth  and  fifth  lumbar,  and  first  and  second 
sacral. 

The  tibial  nerve  enters  the  leg  at  the  lower  border  of  the 
popliteus  muscle,  which  it  supplies,  as  well  as  the  tibiaUs 
posticus,  gastrocnemius,  soleus,and  plantaris,  while  lower  down 
it  supplies  the  flexor  longus  digitorum  and  hallucis.  It  also 
supplies  the  knee-joint,  and,  together  with  the  peroneal  com- 
municating, forms  the  short  saphenous  nerve,  which  supplies 
the  skin  of  the  outer  and  back  parts  of  the  lower  third  of  the 


LOWER  EXTREMITY 


373 


leg,  ankle,  heel,  outer  side  of  foot,  and  little  toe,  and  gives  an 
articular  branch  to  the  ankle.     It  terminates  by  dividing  into 


N,  !to 


FIG.  46. — NERVE-SUPPLY  OF  LOWER  EXTREMITY. 


1.  Ext.  cutaneous. 

2.  Genito-crural. 

3.  Middle  cutaneous. 

4.  Ilio-inguinal. 

5.  Int.  cutaneous. 

6.  Patellar  plexus  from  long  saphenous 

and  ext.,  middle,  and  int.  cutaneous. 

7.  Ext.  popliteal. 

8.  Long  or  int.  saphenous. 

9.  Musculo-cutaneous. 

10.  Short  or  ext.  saphenous. 

11.  Ant.  tibial. 


3.  Ilio-hypogastric. 

4.  Last  thoracic. 


1.  Post,  sacral. 

2.  Post,  luml 

>hypoc 
st  thore 
5    Perforat.  cutan.  of  fourth  sacral. 

6.  Small  sciatic. 

7.  Obturator. 

8.  Ext.  cutaneous. 

9.  Int.  cutaneous. 

10.  Ext.  popliteal. 

11.  Long  saphenous. 

12.  Short  saphenous. 

13.  Int.  calcaneal  of  post,  tibial. 

14.  Int.  plantar  of  post,  tibial. 

15.  Ext.  plantar  of  post,  tibial. 


internal  and  external  plantar  nerves,  the  former  of  which  is 
the  larger,  and  is  homologous  with  the  median  nerve  in  the 
hand,  while  the  latter  is  homologous  with  the  ulnar  (q.v.}. 


374  SURGICAL  ANATOMY 

In  paralysis  of  this  nerve  the  toes  cannot  be  flexed,  nor  the 
ankle  extended  (long  flexors  of  hallux  and  toes,  tibialis  posticus, 
gastrocnemius,  and  soleus).  Adduction  and  inversion  of  the 
foot  are  impaired  (tibialis  posticus),  as  is  likewise  sensation 
over  the  area  supplied. 

The  peroneal  nerve  passes  over  the  outer  head  of  the 
gastrocnemius  to  the  back  of  the  fibular  head.  At  this  part  it 
gives  off  a  sural  branch,  which  supplies  the  skin  over  the  upper 
two-thirds  of  the  leg  posteriorly,  and  a  communicating  branch 
to  form  the  external  saphenous  nerve  with  the  tibial  com- 
municating. The  recurrent  tibial  branch  supplies  the  tibialis 
anticus,  and  tibio-fibular  articulation,  and  knee-joint.  The 
terminal  branches  are  the  anterior  tibial  and  musculo- 
cutaneous,  the  former  supplying  the  tibialis  anticus,  long 
extensors  of  the  hallux  and  toes,  extensor  brevis  digitorum, 
the  three  dorsal  interossei  muscles,  the  ankle,  and  other 
adjacent  joints,  and  the  skin  over  the  adjoining  sides  of  the 
great  and  second  toes. 

The  musculo-cutaneous  nerve  supplies  the  peronei  longus 
and  brevis,  and  the  skin  over  the  lower  third  of  the  leg,  dorsum 
of  the  foot,  and  toes. 

In  paralysis  of  the  nerve  the  foot  droops,  and  can  neither 
be  flexed  nor  abducted  (extensors  of  hallux  and  toes,  and 
peronei),  and  adduction  is  imperfect  (tibialis  anticus).  It 
also  becomes  flattened  from  paralysis  of  the  peroneus  longus. 
Sensation  is  impaired  over  the  affected  area. 


SECTION  V 
UPPER  EXTREMITY 

REGION  OF  THE  SHOULDER— SURFACE  ANATOMY.— This 
region  may  be  divided  into  clavi  pectoral,  deltoid,  and  scapular 
portions.  The  CLAVI  PECTORAL  REGION  is  bounded  by  the 
clavicle  above,  the  sternum  internally,  lower  border  of  the 
pectoralis  major  below,  and  the  groove  between  the  pectoralis 
and  deltoid  externally.  The  skin  is  thin  and  freely  movable, 
while  the  subcutaneous  tissue,  particularly  in  the  female,  is 
generally  abundant.  The  clavicle  forms  a  prominent  land- 
mark, the  acromial  end  being  generally  the  least  prominent 
portion,  while,  when  the  acromio-clavicular  ligaments  are 
relaxed,  it  may  be  very  prominent,  simulating  subluxation. 
While  the  axis  of  the  clavicle  is  normally  directed  outwards 
and  upwards,  so  that  the  sterno-clavicular  articulation  is  in 
line  with  the  head  of  the  humerus,  it  may  in  weakly  persons 
incline  downwards  at  the  outer  end.  The  deltoid  tubercle  is 
a  small  bony  projection,  situated  about  the  centre  of  the  outer 
curve,  on  the  anterior  border,  which,  if  well  developed,  might 
be  mistaken  for  an  exostosis.  A  bursa  frequently  develops 
over  the  outer  part  of  the  clavicle  in  those  who  carry  weights  on 
the  shoulder,  and  lipomas  are  sometimes  met  with  in  the  same 
region.  The  infraclavicular  fossa  lies  under  the  outer  third 
of  the  clavicle,  which  bounds  it  above,  and  is  directed  down- 
wards and  outwards  between  the  pectoralis  major  and  deltoid. 
It  overlies  the  upper  part  of  the  axilla,  lodges  the  cephalic 
vein  and  a  branch  of  the  acromio- thoracic  artery,  and  the 
axillary  artery  may  be  felt  and  compressed  against  the  second 
rib  by  deep  pressure  in  it.  It  is  obliterated  in  subcoracoid 
dislocations  of  the  humerus,  some  fractures  of  the  clavicle, 
axillary  swellings,  and  by  superficial  oedema.  The  coracoid 
process  lies  just  to  its  outer  side,  covered  by  some  fibres  of  the 

375 


376  SURGICAL  ANATOMY 

deltoid.  When  the  arm  hangs  at  the  side  with  the  palm 
directed  forwards,  the  bicipital  groove  also  looks  forward, 
and  lies  midway  between  the  acromial  and  coracoid  processes. 
In  this  position  also  the  acromion,  external  condyle,  and 
styloid  process  of  radius  all  lie  in  the  same  line.  The  lower 
border  of  the  pectoralis  major  constitutes  the  anterior  fold  of 
the  axilla.  The  line  of  the  axillary  artery,  when  the  arm  is 
raised  from  the  side,  runs  from  the  centre  of  the  clavicle  to  the 
inner  side  of  the  coraco-brachialis.  The  upper  border  of  the 
pectoralis  minor  is  indicated  by  a  line  from  the  costo-chondral 
junction  of  the  third  rib  to  the  coracoid.  The  point  of  inter- 
section of  these  two  lines  indicates  the  position  of  the  acromio- 
thoracic  artery.  A  line  from  the  costo-chondral  junction  of  the 
fifth  rib  to  the  coracoid  indicates  the  lower  border  of  the 
pectoralis  minor,  and  the  long  thoracic  artery  which  runs  along 
that  border. 

The  DELTOID  REGION  corresponds  to  the  deltoid  muscle, 
being  limited  above  by  the  outer  third  of  the  anterior  border 
of  the  clavicle,  tip  and  outer  border  of  the  acromion,  and 
lower  border  of  the  spine  of  scapula.  It  extends  almost 
to  the  centre  of  the  humerus.  The  skin  in  this  region  is 
rather  thick  and  coarse,  and  is  bound  to  the  fascia  of  the  under- 
lying muscles  by  fascial  septa.  The  rounded  contour  of  the 
shoulder  depends  on  both  the  deltoid  muscle  and  the  tube- 
rosities  of  the  humerus.  If  the  muscle  be  atrophied  or  the 
head  of  the  bone  displaced,  the  acromion  process,  which 
normally  does  not  form  a  projection,  stands  out  prominently, 
and  the  tip  of  the  fingers  may  even  be  inserted  beneath  it. 
The  junction  of  the  acromion  with  the  inferior  border  of  the 
scapular  spine  is  marked  by  the  acromial  angle,  which  is  often 
the  best  marked  portion  of  the  acromion,  and  is  used  in  taking 
various  measurements.  It  is  useful  to  remember  in  examining 
for  dislocation  that  the  internal  condyle  of  the  humerus 
indicates  the  direction  of  the  articular  surface  of  the  head. 
The  most  prominent  portion  of  the  shoulder  in  front  is  formed 
by  the  great  tuberosity.  The  coracoid  process  lies  just  to  the 
outer  side  of  the  infraclavicular  fossa,  and  is  overlapped  by  the 
anterior  border  of  the  deltoid  muscle.  The  posterior  circum- 
flex artery  and  circumflex  nerve  cross  the  humerus  horizontally 
a  ringer's  breadth  above  the  centre  of  the  vertical  length  oi 
the  deltoid. 


UPPER  EXTREMITY  377 

The  SCAPULAR  REGION  corresponds  to  the  bone,  which 
extends  from  the  second  to  the  seventh  rib,  and  is  divided  by 
the  spine  into  supra-  and  infraspinous  regions.  The  skin  in 
this  region  is  thick,  and  closely  adherent  to  the  dense  subcu- 
taneous tissue,  and  is  frequently  the  seat  of  boils  and  car- 
buncles. The  scapular  spine  forms  a  prominent  landmark, 
and  its  inner  extremity  is  opposite  the  spine  of  the  third  dorsal 
vertebra.  The  vertebral  border  and  spine  of  the  scapula  are 
easily  palpated,  while  the  anterior  border  is  covered  by  the 
infraspinatus  and  teres  muscles.  The  anterior  surface  of  the 
scapula  gives  origin  to  the  subscaptilaris,  which  forms  the 
greater  part  of  the  posterior  axillary  wall.  The  latissimus 
dor  si  forms  the  posterior  fold  of  the  axilla,  and  lies  at  a  lower 
level  than  the  pectoralis  major,  which  forms  the  anterior  fold, 
and  lies  at  the  level  of  the  fifth  rib. 

The  Clavi-peetoral  Region. — The  shoulder  girdle  is  formed 
by  the  clavicle  and  scapula,  the  clavicle  alone  being  articulated 
to  the  trunk  at  the  sterno-clavicular  articulation.  A  few  cases 
of  avulsion  of  the  entire  upper  limb  have  been  recorded,  the  only 
joint  involved  being  the  small  sterno-clavicular  one.  The 
skin  over  the  clavicle  is  freely  movable,  and  hence  frequently 
escapes  wounding  and  penetration  from  fracture,  while  injury 
is  frequently  accompanied  by  severe  pain  from  implication  of 
the  supraclavicular  nerves,  which  may  also  rarely  be  caught  in 
callus  after  fracture,  and  so  cause  persistent  pain.  On  the 
other  hand,  pain  over  the  clavicle  may  be  caused  by  disease 
of  the  upper  cervical  spine,  the  pain  being  referred  along  the 
supraclavicular  branches  of  the  third  and  fourth  cervical 
nerves.  In  addition  to  the  skin,  fascia,  and  superficial 
nerves,  the  anterior  surface  of  the  clavicle  is  covered  by 
platysma  fibres,  and  occasionally  is  crossed  by  the  cephalic 
vein,  or  a  branch  from  it  to  the  external  jugular.  The 
innominate  vein  lies  behind  the  sternal  end  of  the  clavicle,  and 
also  the  bifurcation  of  the  innominate  artery  on  the  right,  and 
the  common  carotid  on  the  left.  These  structures  are  separated 
from  the  bone  by  the  sterno-hyoid  and  thyroid  muscles.  The 
subclavian  vessels  (with  the  vein  most  internal)  and  cords  of  the 
brachial  plexus  lie  behind  the  inner  or  greater  curve  of  the 
clavicle,  from  which  they  are  separated  by  the  subclavius 
muscle  and  axillary  sheath.  Owing  to  its  position  and  the 


378  SURGICAL  ANATOMY 

weakness  of  its  wall,  the  vein  is  most  readily  pressed  on  by 
tumour  or  fracture,  the  subclavius  muscle,  however,  saving  it 
in  many  instances.  In  addition  to  the  structures  mentioned, 
the  suprascapular  and  internal  mammary  arteries,  the  external 
jugular  veins,  the  phrenic  and  'posterior  thoracic  nerve  (to 
serratus  magnus),  omo-hyoid  and  scalene  muscles,  and  apex 
of  lung  lie  behind  the  clavicle. 

The  surfaces  of  both  clavicle  and  sternum  are  covered  with 
fibre-cartilage  at  the  STERNO-CLAVICULAR  ARTICULATION,  and 
a  disc  of  fibre-cartilage  intervenes,  which  is  attached  above 
to  the  clavicle,  and  below  to  the  sternum,  and  generally  divides 
the  joint  into  two  distinct  synovial  compartments. 

The  capsular  ligament  is  attached  both  to  the  clavicle  and 
sternum,  and  the  margin  of  the  plate  of  fibro-cartilage,  and  is 
well  denned  arteriorly  and  posteriorly. 

A  strong  ligamentous  band — the  inter  clavicular  ligament — 
extends  from  the  upper  border  of  the  articular  facet  of  one 
clavicle  to  the  other,  over  the  sternal  notch,  into  which  many 
fibres  are  inserted  ;  and  the  rhomboid  ligament  consists  of  fibres 
directed  upwards  and  outwards  from  the  first  costal  cartilage 
to  the  under  surface  of  the  clavicle.  To  these  two  latter  acces- 
sory ligaments  the  strength  of  the  articulation  is  mainly  due. 
The  joint  permits  of  limited  movement  in  nearly  all  directions, 
and,  when  diseased,  abduction  of  the  arm  is  particularly 
painful,  as  the  joint  surfaces  are  then  brought  most  nearly  into 
apposition.  Forward  movement  is  checked  by  the  posterior 
ligament,  assisted  by  the  anterior  ;  backward  movement  by 
the  anterior,  assisted  by  the  posterior  and  the  rhomboid  ; 
upward  by  the  rhomboid,  interclavicular,  and  interarticular 
cartilage. 

Dislocation  of  the  sternal  end  of  the  clavicle  is  not  common, 
that  forwards  being  the  most  frequent,  and  followed  by  those 
backwards  and  upwards,  the  latter  being  very  uncommon. 
In  the  forward  variety  the  head  of  the  bone  lies  in  front  of  the 
manubrium,  and  carries  the  sterno-mastoid  forwards.  In  the 
backward  dislocation  the  rhomboid  ligament  is  torn  in  addition 
to  the  capsule,  and  the  head  lies  between  the  manubrium  and 
the  sterno-hyoid  and  thyroid  muscles,  sometimes  pressing  on 
the  trachea  or  oesophagus,  causing  dyspnoea  or  dysphagia,  or  on 
the  subclavian  artery  or  innominate  vein.  In  the  upward 
variety  the  head  lies  on  the  manubrium  between  the  sterno- 


UPPER  EXTREMITY  379 

mast  old  and  sterno-hyoid  muscles.  The  dislocations  are 
generally  easily  reduced,  but  difficult  to  retain  in  position. 
This* joint  is  said  to  be  more  frequently  involved  in  pyczmia 
than  any  other.  The  pus  generally  presents  anteriorly, 
though  it  may  burst  posteriorly,  and  so  enter  the  mediastinum, 
and  the  condition  is  not  followed  by  anchylosis,  owing  to  the 
character  of  the  joint  and  the  constant  movement.  Not 
merely  does  the  clavicle  supply  the  only  articulation  between 
the  upper  limb  and  the  trunk,  it  also  plays  an  important  part 
in  regulating  the  position  of  the  shoulder  in  relation  to  the 
chest- wall,  and  gives  attachment  to  important  muscles  both 
of  the  neck  and  of  the  upper  extremity.  Before  discussing 
its  regulating  power,  it  will  be  necessary  to  consider  the 
connections  between  the  clavicle  and  scapula.  These  consist 
of  two  sets  —  acromio-clavicular  articulation  and  coraco- 
clavicular  ligaments. 

The  ACROMIO-CLAVICULAR  JOINT  is  directed  from  before 
backwards,  and  slopes  from  above,  down,  and  inwards,  the 
outer  end  of  the  clavicle  projecting  to  a  varying  extent  above 
the  upper  surface  of  the  acromion  upon  which  it  rests.  An 
incomplete  interarticular  cartilage  generally  exists,  and  there 
is  a  capsular  ligament  best  developed  above  and  below. 

The  CORACO-CLAVICULAR  ATTACHMENT  consists  of  two  liga- 
ments, the  conoid  and  trapezoid,  which  extend  from  the 
posterior  portion  of  the  upper  surface  of  the  coracoid  process 
to  the  conoid  tubercle  and  trapezoid  ridge  respectively  on  the 
under  surface  of  the  clavicle.  A  synovial  bursa  frequently 
exists  between  these  two  ligaments.  These  ligaments  chiefly 
limit  the  movement  of  the  outer  end  of  the  clavicle,  which  is 
fixed  to  and  must  move  with  the  scapula.  When  the  scapula 
moves,  it  carries  with  it  the  clavicle,  which  in  turn  moves  on 
the  sterno-clavicular  joint.  But  for  the  clavicle,  the  scapula,  in 
gliding  round  the  chest-wall  under  the  action  of  the  serratus 
magnus  and  other  muscles,  would  tend  to  lie  close  to  that  wall, 
and  thus,  when  the  scapula  came  forward  on  the  chest,  its 
glenoid  cavity,  instead  of  being  at  right  angles  to  the  long 
axis  of  the  arm,  would  be  directed  forwards  and  inwards,  so  that 
if  the  arm  were  used  to  strike  a  blow,  the  head  of  the  humerus 
would  rest  on  the  posterior  part  of  the  capsule,  instead  of  in 
the  glenoid  cavity,  and  thus  dislocation  would  probably  occur. 
This  tendency  for  the  scapula  to  rotate  on  coming  forwards  is 


380  SURGICAL  ANATOMY 

prevented  by  the  clavicle,  and  as  it  does  so  the  acromio- 
clavicular  joint  comes  into  play,  and  the  angle  between  the 
scapula  and  clavicle  diminishes.  Owing  to  the  shape  of  this 
joint,  dislocation,  when  it  occurs,  is  generally  upwards  and 
frequently  partial.  A  few  cases  of  downward  dislocation  are 
recorded.  The  displacements  are  easily  reduced,  but  difficult 
to  retain  in  position. 

The  clavicle,  owing  to  its  superficial  and  exposed  position, 
its  reception  of  all  shocks  communicated  to  the  upper  ex- 
tremity, its  slenderness  and  early  ossification,  is  more  fre- 
quently fractured  than  any  other  bone,  the  fracture  most 
frequently  occurring  at  the  junction  of  the  middle  and  outer 
thirds.  The  fracture  occurs  here,  as  this  is  the  most  slender 
part  of  the  bone  ;  the  fixed  outer  third  meets  the  more  movable 
inner  two-thirds,  and  the  two  curves  meet  at  this  point.  The 
fracture  is  generally  due  to  indirect  violence,  is  oblique,  and 
runs  from  above,  downwards,  and  inwards,  the  inner  fragment 
maintaining  its  normal  position,  or  having  its  outer  end 
slightly  raised  by  the  clavicular  portion  of  the  sterno-mastoid. 
The  outer  fragment  is  (a)  depressed  by  the  weight  of  the 
limb,  aided  by  the  pectorals  and  latissimus  dorsi ;  (b)  drawn 
inwards  by  the  same  muscles,  assisted  by  the  trapezius, 
rhomboids,  levator  anguli  scapulae,  and  subclavius  ;  (c)  rotated 
on  a  vertical  axis,  so  that  the  broken  end  looks  inwards  and 
backwards,  by  the  serratus  magnus  acting  on  the  scapula, 
assisted  by  the  pectorals. 

The  rotation  is  generally  difficult  to  remedy,  and  shortening 
frequently  results.  A  recumbent  position,  with  a  narrow 
pillow  between  the  shoulders,  helps  in  reducing  the  deformity. 
Fracture  due  to  direct  violence  may  occur  at  any  part  of  the 
bone,  and  is  generally  transverse.  When  about  the  middle 
third,  the  displacement  is  as  above  ;  when  between  the  conoid 
and  trapezoid  ligaments,  there  is  no  displacement ;  when  external 
to  these  ligaments,  the  inner  end  of  the  outer  fragment  is  raised 
by  the  trapezius,  while  the  outer  end  is  drawn  forwards  by 
the  serratus  magnus  and  pectorals.  In  fracture  at  the  inner 
extremity,  the  inner  end  of  the  outer  fragment  is  displaced 
down  and  inwards,  simulating  dislocation.  The  clavicle  has 
been  fractured  by  muscular  violence,  generally  in  the  middle 
third,  probably  due  to  the  action  of  the  deltoid  and  clavicular 
portion  of  the  pectoralis  major.  It  is  the  most  frequent  seat 


UPPER  EXTREMITY  381 

of  greenstick  fracture,  owing  to  its  early  ossification  (the  entire 
shaft  being  bony  at  birth),  and  thick  but  lax  periosteum,  half 
the  cases  of  fractured  clavicle  occurring  before  five  years  of  age. 
The  cords  of  the  brachial  plexus,  the  subclavian  artery  and 
vein,  the  acromio-thoracic  artery  and  internal  jugular  vein, 
and  even  the  lung  may  be  injured  in  fractures  of  the  clavicle. 
The  biceps,  brachialis  anticus,  and  supinator  longus  are 
supplied  by  the  upper  cord  of  the  plexus,  and  may  be 
paralyzed  by  a  blow  on  the  shoulder  (which  may  subsequently 
fracture  the  clavicle),  or  may  be  affected  by  the  carrying  of 
heavy  weights  on  the  shoulder. 

The  Scapular  Region. — The  posterior  scapular  muscles  are 
contained  within  fairly  definite  compartments,  composed  of 
deep  fascia,  which  are  attached  round  their  origins  to  the  bone, 
and  accompany  them  to  near  their  insertions.  The  sheath  of 
the  infraspinatus  and  teres  minor  muscles  is  more  dense  than 
that  of  the  supraspinatus.  These  facial  sheaths  tend  to  limit 
hsemorrhagic  and  purulent  effusions,  and  direct  them  forward 
toward  the  muscular  insertions,  and  they  also  fix  tumours 
growing  from  the  fascia,  and  thus  make  them  resemble 
tumours  springing  from  the  bone.  The  inferior  angle  of  the 
scapula  is  crossed  by  the  latissimus  dorsi,  and  gives  insertion 
to  a  slip  of  the  muscle.  When  the  angle  slips  out  from  under 
the  latissimus,  as  it  does  in  some  injuries,  especially  when  the 
muscular  slip  is  torn,  the  angle  of  the  scapula  projects,  and  the 
upper  limb  is  somewhat  weakened.  On  the  other  hand, 
especially  after  carrying  heavy  weights  on  the  shoulder,  the 
posterior  thoracic,  or  external  respiratory  nerve  (of  Bell) 
may  be  injured,  causing  paralysis  of  the  serratus  magnus. 
When  this  occurs,  the  vertebral  border  and  inferior  angle  of 
the  scapula  project  markedly  from  the  posterior  chest-wall 
(luxation).  Projection  of  the  angle  of  the  scapula  is  also 
generally  marked  in  lateral  curvature  of  the  spine,  the  scapula 
on  the  side  of  the  convexity  of  the  curve  being  affected.  As 
already  noted,  the  carrying  of  heavy  weights  on  the  shoulder 
may  also  lead  to  paralysis  of  the  biceps,  brachialis  anticus,  and 
supinator  longus.  Owing  to  its  position  between  thick 
muscular  pads,  resting  on  the  elastic  chest,  and  its  mobility, 
fracture,  particularly  of  the  body  of  the  scapula,  is  not 
common.  The  part  of  the  bone  most  frequently  fractured 
is  the  acromion  The  acromion  possesses  two  or  three  centres 


382  SURGICAL  ANATOMY 

of  ossification,  ossification  beginning  about  puberty,  and 
junction  with  the  rest  of  the  bone  about  twenty- three ;  but 
sometimes  only  a  fibrous  union  occurs  between  process  and 
spine.  In  such  cases  of  fracture  displacement  is  slight,  owing 
to  the  dense  periosteum  and  fibrous  aponeurosis  of  the 
muscles.  Occasionally  the  fracture  may  involve  the  acromio- 
clavicular  joint.  The  coracoid  is  rarely  broken  in  dislocations 
of  the  head  of  the  humerus  inwards,  and  still  less  frequently 
by  trauma  or  muscular  violence.  It  may  also  be  separated 
as  an  epiphysis  up  to  the  seventeenth  year.  Displacement 
is  generally  slight,  being  limited  by  the  coraco-clavicular 
ligament,  but  may  be  considerable. 

Fracture  of  the  surgical  neck  of  the  scapula  occurs  rarely. 
The  line  of  fracture  is  from  the  suprascapular  notch  to  the 
upper  part  of  the  axillary  border,  nearly  parallel  to  the 
glenoid  cavity,  and  including  the  coracoid  process.  Displace- 
ment is  generally  slight,  owing  to  the  coraco-clavicular  and 
acromio-clavicular  ligaments ;  but  if  these  be  torn,  then 
the  whole  arm  will  be  displaced  downwards,  the  condition 
resembling  a  subglenoid  dislocation,  from  which  it  may  be 
distinguished  by  the  ease  with  which  reduction  is  obtained, 
but  which  is  not  maintained  ;  by  the  fact  that  the  coracoid 
moves  with  the  humerus  ;  by  crepitus,  etc.  Fractures  of  the 
body  of  the  bone  generally  affect  the  blade  below  the  spine, 
little  displacement  occurring. 

The  scapula  is  not  infrequently  the  seat  of  tumours,  which 
generally  grow  from  the  neck,  spine,  or  inferior  angle. 
Sarcoma  is  generally  of  the  periosteal  type,  and  may 
necessitate  removal  of  the  whole  bone,  and  sometimes  of 
the  arm  as  well,  particularly  if  the  joint  be  involved. 
The  removal  is  done  by  making  an  elliptical  incision, 
beginning  over  the  clavicle,  and  ending  over  the  angle  of  the 
scapula.  The  artery  is  tied  before  the  vein,  so  as  to  empty 
the  limb  of  blood,  and  the  supra-,  sub-,  posterior,  and  dorsal 
scapular  vessels  and  acromial  branches  of  the  acromio- 
thoracic  artery  require  ligature. 

The  Deltoid  Region. — The  SKIN  in  this  region  is  thick,  and 
possesses  a  considerable  subcutaneous  tissue,  in  which  lipomata 
not  infrequently  develop,  and  which  occasionally  shift  their 
position  under  gravity  to  perhaps  the  front  of  the  chest.  The 
deltoid  muscle  in  its  sheath  covers  in  the  whole  region.  Under 


UPPER  EXTREMITY  383 

the  deltoid  is  a  quantity  of  loose  connective  tissue,  which  may 
occasionally  be  membranous,  and  exert  an  effect  in  limiting 
abscesses  of  the  joint.  In  this  loose  tissue  are  one  or  more 
bur  see,  which  separate  the  muscles  from  the  underlying 
structures.  The  coracoid  process  gives  attachment  by  its  inner 
border  to  the  pectoralis  minor,  and  by  its  apex  to  the  coraco- 
brachialis  and  short  head  of  the  biceps.  It  gives  attachment 
to  the  coraco-clavicular  ligaments  (conoid  and  trapezoid)  by 
its  upper  surface,  and  by  its  outer  border  to  the  coraco- 
acromial  ligament,  which  is  a  flat  band,  triangular  in  outline, 
uniting  the  acromion  and  coracoid,  and  thus  completing  the 
coraco-acromial  arch.  This  arch  overhangs  and  completes  the 
shoulder-joint,  from  which  it  is  separated  by  the  subacromial 
bursa,  which  lies  between  the  arch  and  the  capsule  with 
tendons  of  the  capsular  muscles.  This  bursa  is  frequently  the 
seat  of  disease,  rendering  abduction  movements  painful. 
When  it  suppurates,  the  pus  may  burst  into  the  loose  sub- 
deltoid  areolar  tissue,  and  simulate  disease  of  the  shoulder- 
joint.  As  the  fascia  covering  in  the  deltoid  and  infraspinati 
muscles  posteriorly  is  dense,  the  pus  generally  presents 
anteriorly.  '  It  may  be  torn  by  twists  of  the  arm,  and  some- 
times communicates  with  the  joint  in  old  people. 

THE  SHOULDER-JOINT.— While  of  the  ball-and-socket 
variety,  the  shoulder- joint  relies  chiefly  upon  muscular  support, 
and  thus,  while  great  latitude  of  movement  is  permitted,  it 
also  is  prone  to  dislocation.  The  coraco-acromial  arch,  with 
its  concavity  directed  downwards,  greatly  strengthens  the 
articulation  against  upward  and  backward  or  forward  dis- 
placements. While  normally  the  head  of  the  humerus  is  only 
separated  from  the  arch  by  the  bursa,  it  may  in  cases  of 
paralysis  of  the  deltoid  and  scapular  muscles  fall  away  from  it, 
permitting  of  the  insertion  of  the  finger  between  arch  and  head. 
The  joint  is  also  supported  by  the  short  scapular  muscles  and 
the  long  head  of  the  biceps.  In  rupture  of  the  latter  the  head 
of  the  humerus  may  be  pulled  up  and  forwards  close  to  the 
coraco-acromial  arch.  Atmospheric  pressure  and  cohesion 
also  assist  in  keeping  the  parts  in  apposition.  Movement  is 
permitted  in  all  directions,  save  direct  adduction,  but 
extension  backwards  is  limited  by  the  head  coming  in  contact 
with  the  coracoid.  The  movements  generally  are  rendered 
more  free  by  the  mobility  of  the  scapula. 


384  SURGICAL  ANATOMY 

The  glenoid  cavity  is  shallow  and  pyriform,  the  apex  being 
directed  upwards.  The  lowest  part  of  the  margin  is  the 
strongest,  and  it  is  more  prominent  on  the  inner  than  on  the 
outer  side,  thus  strengthening  the  weakest  part  of  the  articula- 
tion, the  lower  and  inner,  through  which  part  dislocations  gener- 
ally occur.  When  the  arm  hangs  at  the  side,  two-thirds  of  the 
humeral  head  are  not  in  contact  with  the  glenoid.  The  glenoid  is 
covered  by  hyaline  cartilage,  and  surrounded  peripherally  by 
a  ring  of  nbro-cartilage,  the  glenoid  ligament,  which  deepens 


FIG.  47.     THE  RIGHT  GLENOID  CAVITY,  AND  THE  ADJACENT  LIGAMENTS. 
(From  Buchanan's  "  Anatomy.") 


r.  Capsule  of  acromio-clavicular  joint. 

2.  Coraco-acromial  ligament. 

3.  Trapezoid  ligament. 

4.  Conoid  ligament. 


5.  Glenoid  ligament. 

6.  Capsular  ligament  (cut). 

7.  Long  head  of  biceps. 


the  cavity.  The  supra-  and  infraspinati  and  teres  minor 
muscles  are  inserted  into  the  great  tuberosity  of  the  humerus, 
and  their  tendons  practically  fuse  with  the  capsular  ligament. 
A  projection  of  synovial  membrane  under  the  infraspinatus  is 
The  subscapularis,  which  is  inserted  into  the  lesser 


rare. 


tuberosity,  is  separated  from  the  capsule,  which  is  deficient  at 
this  point,  by  a  bursa — subscapular — which  may  communicate 
with  the  joint.     Apart  from  these  muscles  the  capsule  is  lax. 
The  capsule  is  inserted  above  into  the  rim  of  the  glenoid  fossa 


UPPER  EXTREMITY  385 

and  to  the  glenoid  ligament,  while  below  it  is  inserted  into  the 
anatomical  neck  of  the  humerus  in  front  and  externally,  but  a 
little  distal  to  the  neck  behind  and  internally.  It  is  strength- 
ened by  some  accessory  ligaments,  the  coraco-humeral  running 
from  the  root  of  the  coracoid  to  the  great  tuberosity,  and 
superior,  middle,  and  inferior  gleno-humeral  running  from  the 
glenoid  margin  above  and  in  front  to  the  lesser  tuberosity  and 
neck  of  the  humerus  below.  The  long  head  of  the  biceps  acts  as 
an  accessory  ligament,  being  inserted  above  into  a  small  depres- 
sion at  the  upper  part  of  the  glenoid  fossa  and  to  the  glenoid 
ligament,  and  then,  crossing  the  head  to  the  inner  side  of  the 
summit,  descends  in  the  bicipital  groove.  It  is  invested  in 
a  fold  of  synovial  membrane,  which  forms  a  prolongation 
lining  the  bicipital  groove  as  far  as  the  insertion  of  the 
pectoralis  major  (the  intertubercular  bursa),  and  the  groove  is 
converted  into  a  canal  at  its  upper  part  by  a  series  of  liga- 
mentous  fibres,  the  transverse  humeral  ligament. 

The  shoulder  is  the  most  common  seat  of  dislocations.  By 
a  false  luxation  is  meant  a  displacement  of  the  head,  which 
remains  within  the  capsule  (as  might  occur  in  paralysis  of  the 
muscles) ,  while  in  true  dislocations  the  head  leaves  the  capsule 
through  a  tear  in  the  latter,  which  in  the  shoulder  is  said  always 
to  occur  primarily  at  the  lower  and  inner  aspect,  the  head 
assuming  the  subglenoid  position.  Such  displacements  are 
caused  by  direct  violence  forcing  the  head  downwrards,  or  by 
indirect  violence  when  the  limb  is  abducted.  Generally  the 
head  does  not  remain  in  the  subglenoid  position,  but  is  drawn 
forwards  and  inwards  by  the  pectoralis  major,  so  as  to  rest  under 
the  coracoid.  A  subspinous  dislocation  is  supposed  to  be  due 
to  the  dislocating  force  acting  from  in  front,  and  so  driving  the 
head  backwards.  In  all  dislocations  of  the  shoulder  there  is 
flattening  of  the  deltoid,  owing  to  removal  of  the  subjacent 
head,  so  that  a  straight-edge  touching  the  external  condyle  and 
lying  along  the  axis  of  the  upper  arm  when  at  the  side  will 
also  touch  the  acromion  process.  Normally  the  straight-edge 
lies  nearly  a  finger's  breadth  from  the  acromion.  As  the 
deltoid  is  also  stretched,  there  is  a  tendency  to  abduction  of 
the  arm  from  the  side,  and  this  is  most  marked  in  the  sub- 
glenoid variety,  while  stretching  of  the  biceps  causes  flexion 
and  slight  supination  of  the  forearm.  In  the  normal  condition 
the  patient  can  touch  the  sound  shoulder  with  the  fingers  of 

25 


386  SURGICAL  ANATOMY 

the  affected  limb,  while  the  internal  condyle  of  the  humerus 
touches  the  crest  of  the  ilium  ;  while  in  dislocation,  owing  to 
the  head  lying  much  closer  to  the  thoracic  wall  than  normally 
and  the  stretching  of  the  muscles,  the  lower  end  of  the 
humerus  generally  cannot  be  brought  close  into  the  side,  and 
the  necessary  rotation  is  not  permitted.  The  head  having 
left  the  glenoid  cavity,  there  is  an  increase  in  the  vertical 
circumference  of  the  shoulder ;  but  this  is  of  little  value  as  a 
test,  since  many  swellings  of  the  shoulder  produce  a  similar 
result.  The  vessels  and  nerves  may  be  pressed  on,  especially 
in  the  subglenoid  or  subcoracoid  varieties,  producing  oedema, 
pain,  and  loss  of  powrer,  and  even  in  rare  cases  gangrene.  The 
circumflex  nerve  is  also  occasionally  damaged. 

Much  the  most  common  form  of  dislocation  is  the  SUB- 
CORACOID, the  head  lying  directly  below  the  coracoid  process, 
in  front,  internal  to,  and  a  little  below,  its  normal  position. 
The  posterior  part  of  the  articular  surface  rests  on  the 
neck  of  the  scapula,  the  anatomical  neck  rests  on  the 
anterior  lip  of  the  glenoid  fossa,  and  the  posterior  part  of  the 
great  tuberosity  is  opposite  the  glenoid  cavity.  The  sub- 
scapularis  muscle  going  to  the  lesser  tuberosity  is  stretched 
over  the  humeral  head,  and  may  be  partly  torn,  while 
the  supra-  and  infraspinati  and  teres  minor  are  stretched 
or  torn,  or  the  great  tuberosity  may  be  separated.  The 
long  head  of  the  biceps  is  deflected  down  and  inwards,  and 
may  even  be  torn  from  its  groove,  while  the  short  head  of  the 
biceps  and  the  coraco-brachialis  are  rendered  very  tense,  and 
lie  in  front  of  the  head,  instead  of  to  the  inner  side.  Fre- 
quently the  head  is  rotated  markedly  inwards,  constituting  an 
intracoracoid  dislocation,  the  biceps  tendon  being  markedly 
deflected,  and  the  head  producing  only  a  slightly  marked 
prominence.  While  there  is  actual  lengthening  present,  the 
abduction  produced  frequently  presents  an  apparent  shorten- 
ing, when  a  measurement  is  taken  from  the  acromion  to  the 
external  condyle.  Rarely  the  head  is  carried  farther  inwards 
and  upwards  towards  the  clavicle,  in  extreme  cases  con- 
stituting a  subclavicular  dislocation. 

The  SUBGLENOID  comes  next  to  the  subcoracoid  dislocation 
in  order  of  frequency.  Here  the  head  lies  below  and  a  little 
in  front  of  and  internal  to  its  normal  position,  lying  between 
the  subscapularis  above,  and  the  long  head  of  the  triceps 


UPPER  EXTREMITY  38? 

below,  the  latter  arresting  its  downward  movement.  The 
articular  head  rests  on  the  flattened  portion  of  the  axillary 
border  of  the  scapula,  which  gives  origin  to  the  triceps,  just 
below  the  glenoid.  The  subscapularis  and  spinati  muscles  are 
stretched  or  torn,  but  the  teres  muscles  generally  escape. 
The  deltoid  is  much  stretched,  and  produces  the  marked 
abduction  of  the  limb,  while  the  coraco-brachialis  and  biceps 
are  stretched,  but  not  generally  injured.  Lengthening  is 
present,  but  is  often  masked  by  abduction. 

SUBSPINOUS  DISLOCATION. — In  the  true  subspinous  dis- 
location the  head  rests  on  the  dorsum  scapulae  under  the  spine, 
the  infraspinatus  and  teres  minor  muscles  being  pushed  before 
it,  while  the  subscapularis  is  drawn  across  the  glenoid,  and 
is  frequently  torn.  The  supraspinatus,  biceps,  and  pectoralis 
major  are  rendered  tense,  the  latter  producing  inward  rotation 
and  forward  adduction  of  the  humerus,  while  the  teres  major 
and  latissimus  dorsi  are  relaxed.  The  circumflex  nerve  is 
frequently  torn.  A  modified  subspinous  or  subacromial 
displacement  is  said  to  be  more  common,  the  head  resting 
on  the  posterior  surface  of  the  neck  of  the  scapula. 

In  reducing  dislocations  of  the  shoulder,  especially  those 
of  old  standing,  the  axillary  artery  is  not  infrequently 
damaged,  the  vein  and  nerves  generally  escaping.  The 
glenoid  cavity  is  capable  of  very  considerable  distension, 
the  humerus  being  separated  from  the  glenoid  by  nearly 
J  inch  in  extreme  cases,  and  thus  giving  rise  to  lengthen- 
ing, while  slight  extension  (arm  carried  back)  and  rotation 
inwards  take  place,  possibly  in  part  due  to  the  action  of  the 
latissimus  dorsi.  When  the  joint  is  distended,  the  diverticula 
also  become  affected,  a  swelling  sometimes  appearing  between 
the  pectoralis  major  "and  the  deltoid,  from  distension  of  the 
intertubercular  bursa,  overlaid  by  the  unyielding  biceps 
tendon  ;  and  when  rupture  occurs  it  is  frequently  through  one 
of  the  diverticula  that  it  takes  place,  most  often  through 
the  intertubercular  one.  Here  the  pus  presents  in  front, 
generally  below  the  pectoralis  major  tendon.  When  it 
escapes  through  the  subscapular  bursa,  it  tends  to  spread 
between  the  muscle  and  vertebral  surface  of  the  scapula,  and 
point  at  the  lower  and  back  part  of  the  axilla. 

EXCISION  of  the  shoulder  is  frequently  performed  for 
tubercular  disease,  or  even  rheumatoid  arthritis,  a  false 

25—2 


388  SURGICAL  ANATOMY 

joint,  with  practically  perfect  movement,  generally  resulting. 
A  vertical  incision  is  made  over  the  head  of  the  bone  midway 
between  the  coracoid  and  the  acromion,  the  humerus  being 
fully  rotated  outwards,  so  as  to  remove  the  long  head  of  the 
biceps  from  injury.  This  incision  goes  through  the  super- 
ficial tissues,  deltoid,  and  capsule  of  the  joint,  and  the  head  is 
then  cut  off  with  a  fan-shaped  osteotome,  and  the  wound 
stitched  up.  In  some  cases  of  myeloid  sarcoma  of  the  upper 
end  of  the  humerus  an  amputation  of  the  head  of  the 
bone  through  the  surgical  neck  is  performed,  a  fairly  useful 
limb  resulting. 

AMPUTATION  at  the  shoulder  may  be  performed  by  making 
a  racket-shaped  incision  to  include  a  deltoid  flap,  from  the 
outer  side  of  the  coracoid  down  to  the  lower  border  of  the 
pectoralis  major,  then  outwards  across  the  limb  through  the 
lower  portion  of  the  deltoid  to  the  posterior  axillary  fold, 
the  limb  being  abducted  and  rotated  outwards.  As  the  first 
part  of  this  incision  is  practically  that  for  excision,  it  enables 
the  conditions  of  the  parts  about  the  joint  to  be  examined 
before  proceeding  to  amputate,  in  cases  of  doubt.  The  racket 
is  now  completed  across  the  superficial  tissues  on  the  inner 
side  of  the  limb.  The  deltoid  flap  containing  the  posterior 
circumflex  vessels  and  circumflex  nerve  is  now  raised,  the 
capsular  muscles,  capsule,  and  biceps  tendon  divided,  and  the 
head  disarticulated.  The  triceps,  latissimus  dorsi,  and  teres 
major  are  next  cut,  and  the  limb  being  drawn  from  the  side, 
the  axillary  vessels  may  be  ligatured,  and  then  along  with 
the  nerves,  cephalic  vein,  humeral  branch  of  the  acromio- 
thoracic  artery,  some  fibres  of  the  deltoid  and  biceps  and 
coraco-brachialis,  divided  by  a  transverse  incision. 

THE  AXILLA  (Fig.  50)  is  a  roughly  funnel-shaped  passage 
between  the  neck  and  the  arm,  whose  apex  is  directed  upwards 
and  inwards,  which  is  bounded  in  front  by  the  clavicle  and  sub- 
clavius  muscle,  and  behind  by  the  first  rib  and  first  digitation  of 
the  serratus  magnus,  and  whose  base  corresponds  to  the  hollow 
of  the  armpit.  The  SKIN  over  the  region  presents  numerous 
hairs  and  sebaceous  and  sudoriferous  glands,  in  connection 
with  which  small  abscesses  frequently  arise.  Its  anterior 
wall  is  composed  of  the  pectoral  muscles,  the  pectoralis  major 
enveloped  in  the  thin,  deep  pectoral  fascia,  and  its  lower 
border  extending  between  the  fifth  rib  and  the  middle  of  the 


UPPER  EXTREMITY 


389 


anterior  border  of  the  deltoid.  Between  the  upper  border  of 
the  pectoralis  major  and  the  deltoid  is  a  narrow  groove, 
which  'contains  the  cephalic  vein,  humeral  branch  of  the 
acromio-thoracic  artery,  and  one  or  two  infraclavicular  glands. 
The  pectoralis  minor  forms  with  the  costo-coracoid  membrane 
a  second,  deeper  layer. 

The  costo-coracoid  membrane  extends  from  the  clavicle  and 
subclavius  muscle  above, ,  between  the  chest-wall  internally 


FIG.  48. — COSTO-CORACOID  MEMBRANE. 


1.  Pretracheal     layer,    deep 

cervical  fascia 

2.  Scalenus  anticus. 

3.  Investing      layer,       deep 

cervical  fascia. 

4.  Omo-hyoid. 

5.  Axillary  vein. 

6.  Axillary  artery. 


7.  Clavicle. 

8.  Subclavius. 

9.  Cephalic  vein. 

10.  Costo-coracoid  membrane 

(clavi-pectoral  fascia). 

11.  Pectoralis  major. 

12.  Pectoralis  minor. 

13.  Axillary  fascia. 


14.  Axillary  sheath. 

15.  First  rib. 

1 6.  Subscapularis. 

17.  Teres  major. 

1 8.  Infraspinatus. 

19.  Supraspinatus. 

20.  Trapezius. 

21.  Scapula. 


and  coracoid  process  externally,  to  the  axillary  fascia, 
stretching  between  the  anterior  and  posterior  axillary  folds, 
below,  where  it  fuses  with  subcutaneous  tissues.  On  its 
way  it  splits  to  enclose  the  pectoralis  minor,  and  it  acts 
as  a  suspensory  ligament,  drawing  up  the  skin  of  the  axilla. 
It  is  separated  by  loose  cellular  tissue  from  the  fascia  covering 
the  pectoralis  major,  and  in  this  tissue  lie  branches  of  the 
acromio-thoracic  vessels,  anterior  thoracic  nerves,  and  a  lym- 


390  SURGICAL  ANATOMY 

phatic  gland  belonging  to  the  infraclavicular  group.  The 
portion  above  the  pectoralis  minor  is  perforated  by  the  cephalic 
vein,  branches  of  the  acromio-thoracic  vessels,  and  external 
anterior  thoracic  nerve.  From  its  deep  surface  it  sends  off 
an  expansion  to  the  axillary  vessels. 

The  posterior  wall  is  formed  from  above  downwards  by 
the  subscapularis,  latissimus  dorsi,  and  teres  major  muscles, 
and  the  inner  costal  wall  is  bounded  by  the  five  upper 
ribs,  intercostal  spaces,  and  serratus  magnus,  on  whose 
surface  lies  the  posterior  thoracic  nerve.  The  base  of 
the  passage  or  hollow  of  the  armpit  is  covered  by  skin, 
subcutaneous  tissues,  and  axillary  fascia,  the  latter  rather 
ill-defined,  and  fusing  in  front  with  the  pectoral  fascia ; 
behind  with  that  covering  the  latissimus  dorsi  and  teres 
major  ;  internally  with  the  fascia  of  the  serratus,  and  ex- 
ternally with  the  deep  fascia  of  the  arm.  The  axilla  is  occu- 
pied by  loose  fatty  connective  tissue,  in  which  large  collec- 
tions of  pus  or  blood  may  accumulate,  and  lodges  the  axillary 
vessels,  brachial  plexus,  and  lymphatic  glands. 

The  AXILLARY  ARTERY  extends  from  the  outer  border  of 
the  first  rib  to  the  lower  border  of  the  teres  major  muscle, 
and  is  divided  into  three  parts — above,  behind,  and  below 
the  pectoralis  minor.  Its  course,  and  that  of  the  brachial, 
is  represented  by  a  line  drawn  from  a  point  J  inch  inside 
the  centre  of  the  clavicle,  to  the  centre  of  the  bend  of 
the  elbow  with  the  upper  limb  at  right  angles  to  the 
trunk.  It  is  accompanied  by  the  axillary  vein,  lymphatic 
glands,  and  cords  of  the  brachial  plexus,  the  vessels  being 
enclosed  in  the  axillary  sheath  derived  from  the  deep  cervical 
fascia.  The  first  part  lies  on  the  first  intercostal  space  and 
serratus  magnus  muscle,  beneath  the  clavicular  portion  of  the 
pectoralis  major  and  the  costo-coracoid  membrane,  and  is 
crossed  by  the  cephalic  vein  from  without  inwards.  The  axil- 
lary vein  lies  on  its  inner  anterior  aspect,  and  the  cords  of  the 
brachial  plexus  behind  and  to  the  outer  side.  One  branch,  the 
superior  thoracic,  is  given  off,  which  anastomoses  with  the  supra- 
scapular,  acromio-thoracic,  and  internal  mammary  arteries. 

Ligature  of  the  first  part  is  performed  through  a  slightly 
curved  *  incision,  made  below  the  clavicle  from  inside 
the  coracoid  to  the  sterno-clavicular  articulation,  skin,  sub- 
cutaneous tissue,  platysma,  and  pectoralis  major  being  divided. 


UPPER  EXTREMITY  391 

(This  portion  of  the  pectoralis  major  sometimes  consists  of 
two  planes,  with  an  intervening  cellular  interval.)  The 
pectoralis  minor  is  now  pulled  down,  the  costo-coracoid 
membrane  defined  and  divided  close  to  the  coracoid  process  ; 
the  vein  is  drawn  in,  the  sheath  of  the  vessel  opened,  and  the 
needle  passed  from  within  outwards.  If  the  vein  overlaps 
the  artery,  the  arm  should  be  drawn  down  to  the  side.  In 
dividing  the  costo-coracoid  membrane,  care  must  be  taken 
not  to  cut  the  branches  of  the  acromio-thoracic  artery  and 
external  and  internal  anterior  thoracic  nerves.  Anasto- 
mosis is  as  in  the  third  part. 

The  second  part  is  the  shortest,  and  is  surrounded  by  the 
cords  of  the  brachial  plexus  lying  in  the  positions  indicated 
by  their  names — inner,  outer,  and  posterior.  The  acromio- 
thoracic  and  long  thoracic  branches  are  given  off  near  the 
upper  and  lower  borders  of  the  pectoralis  minor  respectively. 
The  latter  is  also  called  the  external  mammary,  and  supplies 
the  outer  and  deeper  parts  of  the  gland  and  the  pectoralis 
muscles.  Its  vein  is  stated  to  be  a  canalized  vein,  one 
whose  walls  are  rigid  and  do  not  collapse  when  cut,  render- 
ing it  liable  to  suck  in  air  on  inspiration. 

The  third  part  lies  partly  under  the  pectoralis  major 
and  partly  superficially,  and  lies  on  the  latissimus  dorsi 
and  teres  major,  while  the  capsule  of  the  shoulder-joint 
and  coraco-brachialis  lie  externally.  It  is  surrounded  by 
branches  of  the  brachial  plexus,  the  inner  head  of  the 
median  lying  in  front,  the  internal  cutaneous  and  ulnar 
to  the  inner  side,  median  and  musculo-cutaneous  to  the 
outer,  and  musculo-spiral  and  circumflex  posteriorly.  The 
lesser  internal  cutaneous  nerve  lies  to  the  inner  side  of 
the  vein.  The  chief  branches  given  off  are  the  subscapular, 
which  arises  at  the  lower  border  of  the  subscapularis 
muscle,  and  runs  down  and  back  along  the  posterior  fold 
of  the  axilla  with  the  long  subscapular  nerve  ;  the  anterior 
circumflex,  which  passes  out  across  the  surgical  neck  of  the 
humerus  below  the  biceps  and  coraco-brachialis  ;  the  posterior 
circumflex,  which  passes  with  the  circumflex  nerve  backwards 
through  the  quadrilateral  space,  bounded  by  the  subscapularis 
above,  teres  major  below,  long  head  of  the  triceps  internally, 
and  surgical  neck  of  the  humerus  externally,  to  supply  the 
deltoid,  shoulder-joint,  and  humerus. 


392  SURGICAL  ANATOMY 

Ligature  of  the  third  part  is  performed  through  an  incision 
along  the  line  of  the  vessel  (at  the  junction  of  the  middle 
and  anterior  thirds  of  the  axilla),  which  should  not  extend 
beyond  the  lower  border  of  the  teres  major.  The  super- 
ficial tissues  are  divided,  coraco-brachialis  retracted  out- 
wards with  musculo-cutaneous  nerve ;  the  median  nerve 
is  also  drawn  out,  the  vein  and  internal  cutaneous  nerve 
drawn  in,  and  the  vessel  ligatured  between  the  subscapular 
and  circumflex  branches.  Anastomosis  is  between  the 
branches  of  the  axillary  and  those  of  the  thyroid  axis. 
A  muscular  slip  from  the  latissimus  dorsi  to  the  pec- 
toralis  major,  coraco-brachialis  or  biceps  sometimes  exists, 
crossing  the  third  part  of  the  vessels  obliquely,  which  might 
be  mistaken  for  the  coraco-brachialis.  The  axillary  artery 
is  frequently  affected  by  aneurism,  owing  to  its  nearness  to 
the  heart,  its  abrupt  curve,  and  the  communication  of  move- 
ments to  it  from  the  arm,  by  which  it  may  be  injured.  Such 
aneurisms  frequently  grow  rapidly,  and  may  press  on  the 
cords  of  the  brachial  plexus  and  on  the  axillary  vein. 

The  AXILLARY  VEIN  is  formed  by  the  junction  of  the  basilic 
with  the  venae  comites  of  the  brachial  artery.  This  junction 
frequently  occurs  at  the  lower  border  of  the  subscapularis 
muscle,  rendering  the  vein  shorter  than  the  artery.  Some- 
times venae  comites  may  continue  close  up  to  the  clavicle, 
many  cross  branches  existing.  As  the  costo-coracoid  mem- 
brane is  adherent  to  the  vein  above,  maintaining  it  in  a 
patent  condition,  it  bleeds  very  freely  when  cut,  and  is  also 
liable  to  suck  in  air  on  inspiration.  The  vein  is  more  often 
wounded  than  the  artery,  but  the  latter  is  more  liable  to 
injury  from  traction  on  the  upper  limb.  The  relation  of  the 
vein  to  the  first  part  of  the  artery  varies  according  to  the 
position  of  the  limb,  being  inside  and  a  little  in  front  when  the 
limb  hangs  by  the  side,  and  almost  entirely  in  front  when  the 
arm  is  at  right  angles  to  the  trunk.  The  glands  of  the  deep 
axillary  group  are  situated  along  its  antero-internal  aspect, 
and  are  closely  associated  with  it,  rendering  their  removal 
in  cases  of  advanced  carcinoma  difficult,  and  sometimes 
necessitating  removal  of  a  portion  of  the  vein  itself.  The 
lesser  internal  cutaneous  nerve  lies  along  its  inner  side  at  the 
lower  part  of  the  space,  and  it  receives  the  cephalic  vein  a 
short  distance  below  the  clavicle. 


UPPER  EXTREMITY  393 

The  BRACHIAL  PLEXUS  is  derived  from  the  fifth  to  the 
eighth  cervical  and  first  dorsal  nerves,  and  emerges  between 
the  scalenus  anticus  in  front  and  the  scalenus  medius  and 
posticus  behind.  The  fifth  and  sixth  cervicals  unite,  as  do 
the  eighth  cervical  and  first  dorsal,  forming  thus  three  cords  ; 
and  these  again  divide  each  into  two  at  the  level  of  the  entrance 
of  the  axilla.  The  outer  cord  is  formed  of  the  anterior 
divisions  of  the  fifth,  sixth,  and  seventh  cervicals  ;  the  inner 
of  the  anterior  divisions  of  the  eighth  cervical,  and  nearly  all 
of  the  first  dorsal ;  and  the  posterior  of  the  posterior  divisions 
of  all  the  cervical  nerves  involved.  The  outer  cord  gives  off  the 
external  anterior  thoracic,  musculo-cutaneous,  and  outer  head 
of  the  median  ;  the  inner  gives  off  the  inner  head  of  the 
median,  ulnar,  internal  cutaneous,  lesser  internal  cutaneous,  and 
internal  anterior  thoracic  ;  the  posterior  gives  off  the  circum- 
flex, subscapular,  and  musculo-spiral.  The  median  is  the  nerve 
most  frequently  damaged  by  wounds  of  the  axilla,  and  the 
musculo-spiral  the  least.  In  severe  traction  the  connection 
with  the  spinal  cord  is  the  part  most  likely  to  give 
way. 

The    LYMPHATIC    GLANDS    are    classified   in    four    groups  : 

(1)  Anterior    pectoral    group    (5    or    6),    lying    behind    the 
anterior    axillary    fold,    on    the    serratus    magnus.      These 
drain   the    pectoral  region,    outer    two-thirds   of   the   mam- 
mary gland    the  antero-lateral   chest,   and   abdominal   wall. 

(2)  Central    group    (10    to    15),    lying    under    the    axillary 
fascia,   and    draining   the   upper   limb.      (3)    Posterior   sub- 
scapular  group   (5   or  6),  lying  along  the  posterior  axillary 
fold,    with    the    subscapular    artery    and    long   subscapular 
nerve.      (4)  Deep  group   (6   to  10),  lying  along  the  axillary 
vessels,   and   drain-ing  the   upper  limb,    and   communicating 
with   the  glands   of   the   neck  and  mediastinum,  and   other 
axillary   glands.       The   infraclavicular   glands,    consisting   of 
a  few  between  the  pectoralis  major  and  the  deltoid,  between 
the   pectoralis   major   and   minor,    and   along   the   acromio- 
thoracic  artery,  drain  the  outer  side  of  the  arm,  shoulder, 
and  part  of  the  breast.     The  axillary  glands  are  regularly 
affected  secondarily  in  carcinoma  of  the  breast,  and  occasion- 
ally give  rise  to  a  tumour  much  exceeding  in  size  that  from 
which  it  originated.     They  may  also  become  enlarged  from 
tubercular  and  syphilitic  affections,  and  from  sepsis,  while  they 


394  SURGICAL  ANATOMY 

are  also  occasionally  the  seat  of  lymphadenoma  and  lympho- 
sarcoma. 

Axillary  abscesses  may  arise  from  a  penetrating  wound  or 
from  lymphadenitis.  When  the  abscess  is  superficial  to  the 
costo-coracoid  membrane,  it  is  generally  small,  and  points 
either  in  the  infraclavicular  fossa  or  about  the  anterior  axillary 
fold.  An  abscess  under  the  pectoralis  minor  or  costo-coracoid 
membrane  generally  arises  from  gland  infection,  or  disease 
of  the  shoulder-joint  or  rib.  It  cannot  pass  forwards,  owing 
to  the  pectoralis  minor  and  costo-coracoid  membrane  ;  back- 
wards, owing  to  the  insertion  of  the  serratus  magnus  to  scapula; 
inwards,  owing  to  the  chest-wall  ;  outwards,  owing  to  the 
arm  ;  downwards,  owing  to  the  axillary  fascia  ;  and  therefore, 
after  pressing  on  the  axillary  fascia,  ajad  rendering  it  convex 
externally,  instead  of  concave,  it  tends  to  pass  up  into  the 
neck,  and  possibly  to  the  mediastinum.  Sometimes  the  pus 
may  travel  down  the  arm  along  the  vessels.  In  opening 
axillary  abscesses  the  incision  should  be  made  midway  between 
the  anterior  and  posterior  axillary  folds,  so  as  to  avoid  the 
long  thoracic  and  subscapular  vessels,  and  at  the  thoracic 
rather  than  the  humeral  side,  so  as  to  avoid  the  large  vessels. 
The  external  mammary  artery,  however,  might  possibly  be 
wounded  by  this  incision. 

THE  ARM — SURFACE  ANATOMY. — The  region  of  the  arm 
extends  from  the  axilla  to  the  elbow.  The  contour  varies 
according  to  the  muscular  development,  being  cylindrical 
where  the  development  is  poor,  but  flattened  from  side  to 
side  where  the  muscles  are  well  developed,  and  displaying  the 
prominent  mass  of  the  biceps  in  front.  On  either  side  of  the 
biceps  is  a  sulcus,  that  on  the  inner  being  the  more  marked, 
and  extending  from  the  front  of  the  elbow  to  the  posterior 
axillary  fold.  It  indicates  generally  the  course  of  the  basilic 
vein  and  axillary  vessels,  and  separates  the  biceps  and  coraco- 
brachialis  from  the  triceps  above,  and  the  biceps  from  the 
pronator  radii  teres  below.  The  external  sulcus  extends  from 
the  bend  of  the  elbow  to  the  insertion  of  the  deltoid,  indicates 
so  much  of  the  course  of  the  cephalic  vein,  and  separates 
biceps  and  brachialis  anticus  from  triceps  above,  and  biceps 
from  the  supinator  longus  and  radial  extensors  below.  The 
insertion  of  the  deltoid  marks  the  centre  of  the  humeral  shaft 
where  the  cylindrical  upper  joins  the  lower  prismatic  portion, 


UPPER  EXTREMITY  395 

and  the  nutrient  artery  enters  the  bone.  About  this  level 
the  superior  prof un  da  artery  and  musculo-spiral  nerve  cross 
the  back  of  the  bone,  and  the  coraco-brachialis  is  inserted 
and  the  brachialis  anticus  takes  origin.  The  course  of  the 
brachial  artery,  and  also  of  the  median  nerve-,  is  shown  by  a 
line  drawn  from  the  junction  of  the  anterior  and  middle  third 
of  the  outlet  of  the  axilla  to  the  centre  of  the  bend  of  the  elbow, 
when  the  limb  is  extended  and  supinated.  The  same  line 
indicates  the  course  of  the  ulnar  nerve  in  the  upper  third,  after 
which  it  runs  down  and  backwards  with  the  inferior  profunda 
artery  to  the  posterior  aspect  of  the  internal  condyle.  The 
artery  is  superficial,  can  be  easily  felt  and  compressed  by 
pressure  (out  and  backwards  in  upper  two-thirds  and  backwards 
in  lower  one- third)  against  the  humerus,  and  when  athero- 
matous,  is  frequently  visible  pursuing  a  tortuous  course  just 
under  the  superficial  tissues.  The  musculo-spiral  nerve  follows 
the  line  of  the  artery  for  a  short  distance,  and  then  descends 
obliquely  outwards  across  the  back  of  the  arm  to  the  external 
bicipital  sulcus,  which  it  reaches  about  i  inch  below  the 
insertion  of  the  deltoid,  and  follows  to  near  the  external 
condyle. 

The  SKIN  of  the  arm  is  thin,  smooth,  and  very  mobile  in 
front  and  on  the  inner  side,  but  thicker  and  more  adherent 
on  the  outer  and  posterior  aspects.  The  skin  of  the  front  of 
the  arm  is  used  in  Tagliacozzi's  plastic  operation  for  restora- 
tion of  the  nose.  The  looseness  of  the  skin  allows  of  its  being 
easily  drawn  up  by  hand  in  circular  amputation,  and  large 
flaps  may  be  torn  up  in  various  injuries. 

The  loose  fatty  SUBCUTANEOUS  TISSUE  is  directly  continuous 
with  that  of  the  axilla  and  forearm,  and  thus  inflammatory 
infections  easily  -spread  from  one  region  to  the  other.  In 
this  tissue  lie  the  superficial  veins  (cephalic  on  the  outer  and 
basilic  on  inner  side),  small  arterial  twigs,  superficial  lym- 
phatics, and  supracondyloid  lymphatic  gland  (the  latter  about 
2  inches  above  the  elbow  and  immediately  behind  the  internal 
bicipital  sulcus),  and  superficial  nerves — intercosto-humeral, 
lesser  internal  cutaneous,  branches  of  the  musculo-spiral  and 
internal  cutaneous. 

The  DEEP  FASCIA  is  continuous  with  that  of  the  axilla  and 
forearm,  and  forms  a  complete  investing  sheath,  which  is 
thin  in  front  but  thick  behind,  especially  over  the  lower  part 


396  SURGICAL  ANATOMY 

of  the  triceps.  It  sends  in  outer  and  inner  inter  muscular 
septa  to  the  supracondyloid  ridges  of  the  humerus,  thus  dividing 
the  arm  into  anterior  and  posterior  compartments,  of  which 
the  anterior  contains  all  the  muscles  except  the  triceps,  the 
brachial  vessels,  basilic  vein,  median,  internal  cutaneous, 
and  musculo-cutaneous  nerves.  The  posterior  compartment 
contains  the  triceps,  while  the  superior  profunda  artery  and 
musculo-spiral  nerve,  the  inferior  profunda  artery  and  ulnar 
nerve,  and  the  anastomotica  magna  are  common  to  both 
compartments.  While  various  effusions  tend  to  be  limited 
by  these  compartments,  they  may  pass  from  one  compartment 
to  the  other  by  following  these  perforating  structures. 

The  BICEPS  MUSCLE  is  occasionally  ruptured,  the  long  head 
frequently  giving  way,  the  muscle  then  causing  a  prominent 
swelling  in  the  middle  of  the  arm  when  contracted,  while 
the  arm  is  weakened.  In  such  cases  the  humeral  head  tends 
to  be  displaced  upwards  toward  the  coraco-acromial  arch. 
Sometimes  the  tendon  of  the  long  head  is  displaced,  generally 
inwards,  from  its  groove,  the  head  of  the  bone  again  tending 
to  be  drawn  up.  In  some  cases  of  rheumatoid  arthritis  the 
intracapsular  portion  of  the  tendon  has  been  destroyed  by 
friction,  the  lower  portion  acquiring  an  attachment  to  the 
bicipital  groove.  While  the  biceps  muscle  is  free,  the  bra- 
chialis  anticus  is  attached  to  the  bone,  and  hence  in  amputating 
the  former  retracts  more  markedly  than  the  latter.  Where 
the  muscles  are  well  developed  the  biceps  may  considerably 
overlap  the  brachial  artery. 

The  BRACHIAL  ARTERY  extends  from  the  lower  border  of 
the  teres  major  to  the  bend  of  the  elbow.  At  first  it  lies  to 
the  inner  side,  but  ultimately  lies  in  front  of  the  humerus. 
It  is  superficial  save  near  its  termination,  where  it  dips  under 
the  bicipital  fascia,  between  the  supinator  longus  and  pronator 
radii  teres.  Along  with  the  venye  comites  and  median  nerve, 
it  is  surrounded  by  loose  connective  tissue,  in  which  lie  the 
deep  lymphatics  of  the  limb.  Externally  the  vessel  is  in 
relation  to  the  coraco-brachialis  above  and  biceps  below, 
while  it  lies  from  above  downwards  on  the  long  and  internal 
heads  of  the  triceps,  coraco-brachialis  insertion,  and  brachialis 
anticus.  In  its  upper  part  it  is  surrounded  by  nerves,  the 
median  lying  in  front  and  external,  the  ulnar  and  internal 
cutaneous  internally,  and  musculo  -  spiral  behind.  The 


UPPER  EXTREMITY  397 

median  nerve  remains  in  close  relationship,  but  crosses  in  front 
of  the  artery  at  the  middle  of  the  arm  to  the  inner  side.  The 
ulnar*  nerve  leaves  the  artery  in  the  middle  third  of  the  arm, 
and  piercing  the  internal  intermuscular  septum  along  with 
the  inferior  pro  fund  a,  descends  in  the  triceps  to  the  interval 
between  olecranon  and  internal  condyle  posteriorly.  The 
internal  cutaneous  nerve  also  accompanies  the  artery  in  the 
upper  third,  and  then,  piercing  the  brachial  aponeurosis, 
divides  into  superficial,  anterior,  and  posterior  branches. 
The  musculo-spiral  nerve  soon  leaves  the  artery,  and  inclines 
back  and  outwards  behind  the  humerus  in  the  musculo-spiral 
groove,  along  with  the  superior  profunda  artery.  At  the 
outer  border  of  the  humerus  it  pierces  the  external  inter- 
muscular  septum,  and  descends  in  the  anterior  compartment 
between  the  brachialis  anticus  and  extensor  carpi  radialis 
longior.  The  close  relationship  of  the  brachial  vessel  to 
various  nerves,  and  particularly  the  median,  explains  the  pain 
frequently  caused  by  the  application  of  tourniquets.  The 
musculo-spiral  nerve  is  frequently  damaged  by  contusion  and 
fracture,  the  latter  damaging  the  nerve  either  at  the  time  of 
injury  or  by  subsequent  callus  It  is  frequently  paralyzed 
by  pressure,  as  in  sleeping  with  the  arm  over  the  back  of  a 
chair,  and  in  crutch  paralysis,  the  ulnar  suffering  next  most 
frequently. 

The  artery  is  accompanied  by  vencz  comites,  the  inner 
being  generally  the  larger,  connected  by  numerous  branches, 
crossing  the  vessel  both  in  front  and  behind.  At  the 
elbow  the  vessel  is  crossed  by  the  median  basilic  vein,  the 
bicipital  fascia  intervening.  In  the  lower  part  of  the  arm  the 
basilic  lies  above  the  artery,  separated  from  it  by  the  deep 
fascia,  while  in  the  upper  part  of  the  arm  the  basilic  vein 
pierces  the  deep  fascia,  and  lies  internal  to  the  artery.  The 
chief  branches  of  the  artery  are  the  two  profunda  arteries 
already  described,  the  former  arising  about  ij  inches  behind 
the  commencement  of  the  artery,  and  the  latter  about  the 
middle  of  the  arm  ;  the  nutrient  branch,  given  off  about  the 
centre  of  the  arm,  but  sometimes  from  the  superior  profunda  ; 
the  anastomotica  magna,  given  off  2  inches  above  the  elbow, 
which  runs  in  across  the  brachialis  anticus  behind  the 
median  nerve,  and  bifurcates  into  the  anterior  and  posterior 
branches.  There  are  also  numerous  small  muscular  branches. 


398  SURGICAL  ANATOMY 

The  vessel  is  not  often  wounded,  owing  to  its  protected 
position. 

Abnormalities  are  of  sufficient  frequency  to  require  attention. 
Most  frequently,  when  abnormal,  the  brachial  artery  divides 
in  the  upper  third  of  the  arm,  the  two  vessels  then  running 
together  to  the  elbow,  where  they  become  radial  and  ulnar, 
or  one  may  divide  into  radial  and  ulnar,  and  the  other  form 
a  common  interosseous.  Frequently  one  of  the  two  brachial 
arteries  (the  vas  aberrans)  lies  superficial  to  the  median 
nerve,  and  lower  down  may  pass,  along  with  the  nerve,  under 
a  process  of  bone  arising  from  the  inner  side  of  the  humerus, 
2  inches  above  the  epicondyle,  called  the  supracondyloid 
process, 

LIGATURE  OF  THE  BRACHIAL  artery  may  be  required  for 
injury  to  the  vessel  itself,  or  its  larger  branches  in  the  forearm 
or  hand,  and  is  most  frequently  performed  in  the  middle  of 
the  upper  arm.  An  incision  2j  inches  long  is  made  in  the  line 
of  the  artery,  the  limb  being  held  abducted,  and  not  supported 
underneath,  as  the  triceps  is  then  apt  to  be  pushed  forward 
and  simulate  the  biceps.  Skin,  superficial  and  deep  fascia 
are  cut  through,  the  biceps  and  coraco-brachialis  and  median 
nerve  are  drawn  outwards,  the  ulnar  nerve  and  basilic  vein, 
if  seen,  kept  to  the  inside,  and  the  vessel  ligatured.  A  large 
inferior  profunda  has  been  mistaken  for  the  main  vessel,  and 
the  median  nerve  lying  on  the  vessel  and  receiving  com- 
municated pulsation  from  it  might  similarly  be  mistaken. 
Ligature  in  the  upper  third  is  similar,  the  basilic  vein,  ulnar 
and  internal  cutaneous  nerves  being  displaced  inwards,  and 
the  coraco-brachialis  and  median  nerve  outwards.  Ligature 
at  the  bend  of  the  elbow  is  done  through  an  oblique  incision 
along  the  inner  border  of  the  biceps  tendon,  the  superficial 
tissues  being  divided,  the  median  basilic  vein  drawn  inwards, 
the  bicipital  fascia  divided  as  far  as  is  necessary,  and  the 
artery  thus  isolated  and  ligatured.  The  median  nerve  here 
lies  to  the  inside,  at  the  junction  of  the  inner  and  middle  third; 
the  biceps  tendon  lies  outside  the  artery,  which  lies  at  the  centre 
of  the  elbow ;  and  the  musculo-spiral  nerve  lies  outside  it,  at 
the  junction  of  the  outer  and  middle  third.  There  is  a  free 
anastomosis  at  the  elbow  between  the  profunda  vessels  and 
anastomotica  magna  above,  and  the  anterior  and  posterior 
ulnar  recurrents,  radial  recurrent,  and  interosseous  recurrent 


UPPER  EXTREMITY  399 

below.  Where  ligature  is  performed  above  the  profunda 
vessels,  the  anastomosis  occurs  between  the  circumflex  vessels 
above*  and  the  ascending  branches  of  the  superior  profunda 
below. 

The  HUMERUS  is  cylindrical  above  its  centre,  then  pris- 
matic, and  finally  flattened  antero-posteriorly,  presenting 
marked  lateral  supracondyloid  ridges,  which  give  attachment 
to  the  intermuscular  septa.  The  principal  nutrient  foramen 
is  situated  on  the  inner  side,  about  the  centre  of  the  shaft,  and 
is  directed  downwards  for  about  2  inches  before  opening  into 
the  medullary  cavity.  Sometimes,  however,  the  foramen 
is  situated  posteriorly  in  the  musculo-spiral  groove,  the  nutrient 
vessel  then  coming  off  the  superior  profunda.  A  rough  eleva- 
tion at  the  middle  of  the  outer  side  indicates  the  position  of  the 
insertion  of  the  deltoid  (deltoid  tubercle),  and  the  musculo-spiral 
groove  is  evident  on  the  posterior  aspect.  As  already  pointed 
out,  the  internal  condyle  indicates  the  direction  of  the  articular 
facet  of  the  head,  and  the  external  condyle  is  in  the  same  straight 
line  as  the  great  tuberosity.  These  points  are  of  importance 
in  relation  to  dislocation,  fractures,  and  excisions.  Above 
the  insertion  of  the  deltoid  most  of  the  muscles  surrounding 
the  humerus  do  not  possess  osseous  insertions,  and  thus 
retract  readily  when  cut,  whereas  below  that  point  the  triceps 
and  brachialis  anticus  do  not  retract  much  when  cut,  owing 
to  their  osseous  attachments.  The  upper  end  of  the  humerus 
presents  the  hemispherical  head,  shallow  anatomical  neck, 
the  two  tuberosities,  and  the  surgical  neck.  The  surgical 
neck  is  that  portion  which  lies  below  the  tuberosities,  but  above 
the  insertions  of  the  latissimus  dorsi  and  teres  major  muscles. 

The  circumflex  nerve  and  posterior  circumflex  artery  emerge 
from  between  the,  two  teres  muscles,  and  wind  horizontally 
round  the  bone  at  the  surgical  neck.  The  nerve  supplies  the 
joint,  the  deltoid  and  teres  minor  muscles,  and  the  skin  over 
the  lower  two-thirds  of  the  shoulder  and  upper  part  of  the 
triceps,  thus  securing  agreement  between  the  moving  force 
and  the  parts  moved.  This  distribution  of  the  circumflex 
nerve  is  an  illustration  of  Hilton's  Law  : — A  nerve  trunk, 
supplying  a  given  joint,  also  supplies  the  muscles  moving 
that  joint,  and  the  integument  covering  their  insertions. 
The  nerve  may  be  damaged  by  injury  to  the  shoulder,  and 
more  frequently  by  fracture  of  the  surgical  neck  or  disloca- 


400  SURGICAL  ANATOMY 

tion,  particularly  backwards,  or  by  tumours  of  the  upper 
end  of  the  humerus.  It  may  also  be  affected  by  neuritis 
from  affections  of  the  shoulder-joint.  In  all  these  cases 
paralysis  of  the  deltoid  is  apt  to  result. 

Fractures  of  the  Humerus. — Those  which  occur  at  the 
UPPER  END  may  be  classified  as  (a)  anatomical  neck ; 
(b)  through  the  tubercles ;  (c)  separation  of  the  upper 
epiphysis  ;  (d)  surgical  neck. 

(a)  Anatomical  Neck. — This  is  a  rare  form  of  fracture.     As 
the    capsule    extends    beyond   the    anatomical    neck    below, 
this  fracture  is  partly  intracapsular.     If  entirely  separated, 
the  head  dies  ;  but  if  it  is  impacted  into  the  broad  upper  end 
of  the  shaft,  or  the  reflected  fibres  from  the  capsule  remain 
intact,  it  may  live.     The  deltoid  may  be  slightly  flattened, 
and  the  upper  end  of  the  lower  fragment  projected  slightly 
forwards  and  inwards. 

(b)  Fractures    through  the  tubercles   frequently   cause   but 
little  displacement,  owing  to  the  broad  bone  surfaces  and  the 
muscular  insertions  through  which  the  fracture  passes.     There 
are  three  epiphyses  for  the  upper  end  of  the  humerus — one  for 
the  head,  and  one  for  each   tuberosity,  which  fuse  together 
about  the  fifth  and  join  the  shaft  about  the  twenty-first  year. 

(c)  Separation  of  the    upper  epiphysis  occurs  just  about  the 
position   of   fracture   through   the   surgical   neck.     Displace- 
ment is  generally  slight  owing  to  the  broad  surfaces,  the  upper 
end  of  the  lower  fragment  perhaps  forming  a  slight  projection 
below  the  coracoid   process.     Marked  shortening  is  apt  to 
follow  this  fracture,  as  the  humerus  grows  chiefly  from  this 
upper  epiphysis. 

(d)  Surgical   Neck. — Fracture    in    this   situation    is    fairly 
common,  and  impaction  may  occur,  the  lower  being  driven 
into  the  upper  fragment.     While  there  may  be  a  tendency 
for  the  upper  fragment  to  be  abducted  and  rotated  outwards 
by  the  spinati  and  teres  minor  muscles,  and  for  the  upper 
end  of  the  lower  fragment  to  be  drawn  upwards  by  the  deltoid, 
biceps,    coraco  -  brachialis,    and    triceps,    and    inwards    and 
forwards  by  the  great  pectoral,  there  is  often  little  or  no 
displacement. 

The  shaft  ossifies  from  a  single  centre,  and  is  partially 
ossified  at  birth.  FRACTURES  OF  THE  SHAFT  may  be  classified 
according  as  they  occur  above  or  below  the  insertion  of  the 


UPPER  EXTREMITY  401 

deltoid.  They  are  generally  due  to  direct  violence,  and 
displacement  depends  more  upon  the  fracturing  force  than  on 
muscufar  action.  In  fracture  above  the  insertion  of  the  deltoid 
the  lower  end  of  the  upper  fragment  is  drawn  in  by  the  pec- 
loralis  major,  teres  major,  and  latissimus  dorsi,  while  the 
upper  end  of  the  lower  fragment  is  drawn  up  by  the  biceps, 
coraco-brachialis,  and  triceps,  assisted  by  the  deltoid,  which 
also  throws  it  outwards.  In  fracture  below  the  insertion  of 
the  deltoid  the  tendency  to  displacement  from  muscular  action 
is  less  than  in  that  above  the  deltoid  insertion.  The  lower 
end  of  the  upper  fragment  is  carried  outwards  by  the  deltoid, 
and  the  upper  end  of  the  lower  fragment  upwards  by  the 
biceps  and  triceps.  Fracture  by  muscular  action  occurs 
generally  below  the  insertion  of  the  deltoid.  These  fractures 
of  the  shaft  are  stated  to  be  very  frequently  followed  by  non- 
union, but  this  is  probably  due  to  the  use  of  faulty  apparatus, 
which  does  not  fix  the  shoulder  and  elbow  joints,  and  to  dipping 
of  muscular  tissue  between  the  broken  ends.  The  most 
common  complication  of  fracture  of  the  shaft  is  drop-wrist, 
due  to  injury  to  the  musculo -spiral  nerve,  either  at  the  time 
of  the  accident  or  subsequently  from  involvement  in  callus. 

FRACTURES  OF  THE  LOWER  END  OF  THE  HUMERUS.— 
(a)  Transverse  supracondyloid  ;  (b)  T-shaped  fracture  ; 
(c)  fractures  of  condyles  ;  (d)  separation  of  lower  epiphysis. 
All  of  these  fractures  occur  more  frequently  in  young  subjects. 

(a)  The    transverse    supracondyloid    explains    itself.     It    is 
generally  oblique  from  above  and  behind,   downwards  and 
forwards,  and  results  generally  from  a  blow  on  the  elbow  ; 
the  lower  fragment,  with  the  bones  of  the  forearm,  is  displaced 
backwards  and  upwards,  the  triceps,  biceps,  and  brachialis 
anticus  assisting. 

(b)  In  the  T-shaped  fracture  there  is,  in  addition  to  the 
transverse  fracture  described  in  (a) ,  a  vertical  limb,  which  runs 
down  between  the  condyles  into  the  joint.     It  also  is  generally 
produced  by  falling  on  the  elbow,  which  is  flexed. 

(c)  In  fractures  of  the  condyles  the  line  of  fracture  generally 
lies  above  the  epicondyle  and  outside  the  joint,  and  then 
enters    the    articulation    about    the    trochlear    surface.     In 
fracture  of  the  internal  condyle  displacement  upwards,  back- 
wards,  and  inwards   may   occur,   the   ulna   going  with   the 
condyle      Displacement  in  fracture  of   the   external  condyle 

26 


402  SURGICAL  ANATOMY 

is  generally  slight.  The  epicondyles  may  be  chipped  off,  the 
internal  suffering  more  frequently,  as  it  exists  as  a  distinct 
epiphysis  until  about  the  eighth  year.  Displacement  is 
generally  slight,  but  the  ulnar  nerve  may  be  damaged  by 
fracture  of  the  internal  epicondyle. 

(d)  The  lower  end  of  the  humerus  presents  (a)  an  epiphysis 
for  capitellum  and  outer  half  of  trochlea.  (b)  One  for  re- 
mainder of  the  trochlea.  (c)  One  for  the  external  condyle. 
These  unite  to  form  the  lower  epiphysis,  which  forms  an 
irregular  line  running  between  the  two  condyles,  and  unites 
to  the  shaft  about  the  seventeenth  year.  The  internal 
epicondyle  has  a  separate  epiphysis,  and  does  not  join  the 
shaft  until  about  the  eighteenth  year.  The  epiphysis  is 
almost  entirely  within  the  capsule,  and  there  is  consequently 
in  separation  generally  only  slight  backward  displacement. 
As  the  humerus  grows  chiefly  from  the  upper  epiphysis,  this 
accident  is  not  commonly  followed  by  much  shortening,  and, 
indeed,  marked  shortening  does  not  even  follow  excision  of 
the  elbow  with  complete  removal  of  this  epiphysis,  unless 
performed  at  an  early  age. 

It  is  a  general  rule  that  the  epiphysis  toward  which  the 
nutrient  artery  is  directed  unites  first,  and  also  that  in  the 
foetal  position,  with  both  upper  and  lower  extremities  flexed, 
all  the  nutrient  vessels  point  downwards.  Hence,  in  the 
humerus  the  nutrient  vessel  is  directed  downwards,  and  the 
lower  epiphysis  unites  first.  The  nutrient  vessel  divides 
into  ascending  and  descending  branches  on  reaching  the 
medulla,  which  rapidly  break  up  into  a  fine  capillary  anasto- 
mosis. The  bone  also  receives  blood-supply  from  numerous 
vessels  entering  the  foramina  at  the  extremities  of  the  bone 
and  from  the  periosteum,  and  all  of  these  systems  anastomose. 

Acute  osteomyelitis  is  discussed  in  connection  with  affections 
of  the  lower  limb.  It  occasionally  affects  the  humerus. 
Chronic  microbic  infection  of  long  bones  may  be  either  due 
to  tubercle  or  syphilis.  The  former  generally  attacks  the 
epiphyses,  causing  ulceration  or  caries  of  bone,  rarely  invades 
the  diaphysis,  and  regularly  affects  the  joint,  giving  rise  to 
tubercular  synovitis,  ulceration,  and  shedding  of  cartilage, 
sinus  formation,  anchylosis,  etc.  Syphilis  affects  bone  in 
many  ways,  a  chronic  osteitis  and  periostitis,  with  formation 
of  nodes  on  the  surface  of  the  shaft,  being  one  of  the  most 


UPPER  EXTREMITY  403 

common  (occurs  generally  in  tibia).  The  humerus  may 
also  be  affected  by  sarcoma,  either  myeloid,  spindle-  or  round- 
celled:  The  former  type  generally  occurs  within  the  ends  of 
long  bones  (head  of  humerus),  while  the  latter,  which  is 
much  more  malignant,  generally  begins  on  the  surface  of  the 
shaft,  probably  in  the  periosteum.  While  the  myeloid 
sarcoma  may  be  sometimes  successfully  removed  by  a  local 
operation,  the  periosteal  type  demands  disarticulation  at  the 
shoulder. 

Amputation  through  the  arm  is  generally  performed  by  a 
modified  circular  method,   two   short   antero-posterior  flaps 


FIG.  49. — OUTLINE  DIAGRAM  OF  TRANSVERSE  SECTION  OF  UPPER  ARM 
IN  THE  MIDDLE  THIRD. 

(Modified  from  Heath.) 

1.  Biceps.                                 6.  Brachial  vessels.  n.  Superior  prof  unda  vessels. 

2.  Brachialis  anticus.            7.  Ulnar  nerve.  12.  Musculo-spiral  nerve. 

3.  Triceps.                               8.  Internal  cutaneous  nerves.  13.  Musculo  cutaneous  nerve. 

4.  Triceps.                              9.  Basilic  vein.  14.  Cephalic  vein. 

5.  Median  nerve.  10.   Inferior  profunda  vessels 

of  skin  and  cellular  tissue  (z\  inches  long)  being  raised 
and  retracted,  the  muscles  then  cut  circularly,  and  also  re- 
tracted, and  then  the  bone  cut  as  high  up  as  possible.  As  the 
biceps  retracts  markedly,  it  is  generally  best  to  cut  it  first 
about  the  level  of  the  skin  incision,  and  then  cut  the  other 
muscles  higher  up  If  the  amputation  be  about  the  middle 
of  the  arm,  the  nutrient  artery  may  give  a  little  trouble.  In 
arranging  the  flaps  the  arm  should  be  well  rotated  outwards, 
and  then  in  the  anterior  segment  are  the  biceps  and  bra- 
chialis  anticus,  with  the  musculo-cutaneous  nerve  between 

26—2 


404 


SURGICAL  ANATOMY 


them,  and  a  small  portion  of  the  triceps  ;  the  brachial  vessels, 
median  and  ulnar  nerves,  and  inferior  profunda  artery. 
The  basilic  vein  and  internal  cutaneous  nerve  are  found 
about  the  inner  border,  and  the  cephalic  vein  about  the  outer 
border  of  the  skin  flap.  In  the  posterior  segment  are  the 
triceps,  superior  profunda  artery,  and  musculo-spiral  nerve. 

THE  ELBOW— SURFACE  ANATOMY.— The  lower  end  of  the 
biceps  muscle  and  its  tendon  form  a  tapering  mass  in  the 


.  \   \  \      S 

IS  17  1(5  15       14 


FIG.  50. — THE  AXILLARY  SPACE,  AFTER  REFLECTION  OF  THE  PECTORALIS 
MAJOR;  AND  THE  SUBCLAVIAN  TRIANGLE. 

(From  Buchanan's  "  Anatomy.") 


1.  Trapezius. 

2.  Suprascapular  vessels. 

3.  Transverse  cervical  artery. 

4.  Posterior  belly  of  omo-hyoid. 

5.  Scalenus  anticus. 

6.  Sterno-cleido-mastoid. 

7.  Clavicle  in  section. 

8.  Subclavius. 

9.  Axillary  artery. 
TO.  Axillary  vein. 

ii.  Pectoralis  major  (cut). 


12.  Pectoralis  minor. 

13.  Outer  head  of  median  nerve. 

14.  Inner  head  of  median  nerve. 

15.  Internal  cutaneous  nerve. 

16.  Ulnar  nerve. 

17.  Axillary  vein. 

18.  Nerve  of  Wrisberg. 

19.  Deltoid. 

20.  Mu«culo-cutaneous  nerve. 

21.  Cephalic  vein. 

22.  Brachial  plexus. 


centre  of  the  elbow,  and  is  separated  by  an  angular-shaped 
hollow  from  a  mass  on  the  outer  side,  consisting  of  supinator 
longus  and  extensor  muscles,  and  from  a  mass  on  the  inner, 
consisting  of  pronator  radii  teres  and  flexor  muscles.  The 
diverging  limbs  of  the  angle  run  into  the  outer  and  inner 
bicipital  sulci,  and  its  apex  corresponds  to  the  point  where 
the  biceps  tendon  dips  down  to  its  insertion.  In  this  position, 


UPPER  EXTREMITY  405 

but  external  to  the  biceps  tendon,  the  median  vein  of  the 
forearm  is  joined  by  the  deep  median  vein,  and  then  divides 
into  median  basilic,  which  crosses  the  biceps  tendon  to  occupy 
the  inner  sulcus,  and  median  cephalic,  which  occupies  the 
outer  sulcus.  The  median  basilic  is  joined  by  the  posterior 
ulnar  vein  above  the  internal  condyle,  to  form  the  basilic 
vein,  and  the  median  cephalic  is  joined  by  the  radial  vein  at 
the  level  of  the  external  condyle,  to  form  the  cephalic  vein. 
More  deeply  placed  in  the  inner  groove  are  the  brachial 
vessels  and  median  nerve,  while  in  the  outer  groove,  deeply 
placed,  are  the  terminations  of  the  musculo-spiral  nerve  and 
superior  profunda  artery.  The  outer  border  of  the  biceps 
tendon  is  generally  easily  palpated,  but  the  inner  border  is 
somewhat  obscured  by  the  bicipital  fascia.  The  fold  of  the 
elbow,  convex  below,  extends  between  the  two  condyles,  a 
little  above  the  joint  line.  The  condyles  form  good  land- 
marks, the  internal  being  more  prominent  and  less  rounded 
than  the  outer,  and  their  prominence  is  frequently  taken 
advantage  of  in  applying  traction  from  the  elbow.  The 
olecranon  is  also  well  marked,  lying  nearer  the  internal  than 
the  external  condyle.  A  depression  between  internal  condyle 
and  olecranon  lodges  the  ulnar  nerve,  which  may  frequently 
be  felt,  and  the  posterior  ulnar  recurrent  artery.  To  the 
outer  side  of  the  olecranon  and  below  the  external  condyle 
is  a  depression,  best  marked  when  the  limb  is  extended,  in 
which  the  head  of  the  radius  may  be  felt,  and  which  marks 
the  separation  of  anconeus  from  radial  extensors  of  the 
carpus  and  supinator  longus.  A  line  joining  the  two  condyles 
is  at  right  angles  to  the  axis  of  the  humerus.  In  extension 
the  tip  of  the  olecranon  may  lie  a  little  above  this  line,  but 
in  flexion  is  below  i-t,  normally  forming  when  flexed  to  a  right 
angle  an  equilateral  triangle  with  the  condyles  of  the  humerus. 
The  line  of  the  elbow-joint  as  a  whole  is  equivalent  to  about 
two-thirds  of,  and  is  not  parallel  to,  the  intercondylar  line  ; 
for  while  the  radio-humeral  joint  is  parallel,  and  is  situated 
f  inch  below  the  external  condyle,  the  ulnar-humeral  joint 
slopes  downwards  and  inwards,  and  is  fully  i  inch  below  the 
internal  condyle  at  its  inner  extremity.  Hence  in  extension 
the  forearm  is  at  a  slight  angle  with  the  upper  arm,  the  apex 
directed  inwards. 

Tne  SKIN  IN   FRONT  OF  THE   ELBOW  is   thin  and  mobile, 


406 


SURGICAL  ANATOMY 


FIG.  51.-  SUPERFICIAL  DISSECTION  OF  THE  FRONT  OF  THE  LEFT  ELBOW. 
(From  Buchanan's  "  Anatomy.") 


1.  Brachialis  anticus. 

2.  Biceps. 

3.  Cephalic  vein. 

4.  Musculo-cutaneous  nerve. 

5.  Median  cephalic  vein. 

6.  Radial  vein. 

7.  Deep  median  vein. 

8.  Radial  recurrent  artery. 

9.  Radial  artery  and  venae  comites. 

10.  Median  vein. 

11.  Brachio-radialis. 

12.  Pronator  radii  teres. 

13.  Anterior  ulnar  vein. 


14.  Ulnar  artery  and  venae  comites. 

15.  Bicipital  fascia. 

1 6.  Median  basilic  vein. 

17.  Anterior  branch  of  internal  cutaneous 

nerve. 

18.  Posterior  ulnar  vein. 

19.  Posterior  branch  of  internal  cutaneous 

nerve. 

20.  Brachial  artery  and  venae  comites. 

21.  Median  nerve. 

22.  Basilic  vein. 

23.  Internal  cutaneous  nerve. 


frequently  possessing  little  subcutaneous  fat,  the  superficial 
veins  being  visible  through  it.  They  may  be  rendered 
more  prominent  by  moderate  constriction  of  the  arm.  Their 


UPPER  EXTREMITY  407 

arrangement,  forming  a  capital  M  by  the  median  dividing 
into  median  basilic  and  cephalic,  which  are  joined  respectively 
by  ulrtar  and  radial,  has  already  been  described,  but  the 
arrangement  is  not  constant.  The  median  basilic  is  the  most 
constant  and  least  movable  of  these  veins,  and,  further,  having 
received  the  blood  of  the  deep  median,  is  the  largest,  while 
it  has  also  thick  walls,  and  was  therefore  generally  selected 
for  venesection  (or  phlebotomy).  It  crosses  the  biceps  tendon 
and  bicipital  fascia,  and  is  thus  separated  from  the  brachial 
vessels  and  median  nerve.  Notwithstanding  the  separation, 
the  artery  used  occasionally  to  be  wounded  in  venesection, 
an  arterio-venous  aneurism  resulting  ;  and  as  the  superficial 
lymphatics  accompany  the  veins,  acute  lymphangitis  was  also 
not  uncommon.  The  lymphatic  gland  lying  above  the  internal 
condyle,  which  receives  lymph  from  the  inner  side  of  the 
forearm  and  inner  fingers,  is  the  lowest  in  the  upper  extremity, 
and  has  already  been  mentioned.  Injury  to  nerves  was 
sometimes  occasioned  in  venesection,  the  internal  cutaneous, 
when  involved,  causing  a  neuralgia,  while  inclusion  of  fila- 
ments of  the  musculo  -  cutaneous  (lying  over  the  median 
cephalic)  in  the  scar  has  led  to  reflex  irritation,  and  contraction 
of  the  biceps  and  brachialis  anticus,  which  are  supplied  by  the 
same  spinal  segment,  a  flexed  arm  resulting.  The  ante- 
cubital  fossa  is  the  triangular  depression  in  front  of  the  elbow. 
Under  the  deep  fascia  lie,  centrally,  the  biceps  tendon,  with 
the  brachial  artery,  accompanied  by  its  venae  comites,  to  its 
inner  side.  (The  bicipital  fascia,  which  covers  the  artery,  is 
a  strongly  developed  portion  of  the  deep  fascia,  extending  from 
the  biceps  tendon  to  the  inner  side  of  the  arm.)  To  the 
inner  side  of  the  artery,  at  the  junction  of  the  inner  and 
middle  third  of  the  elbow,  lies  the  median  nerve.  Both  artery 
and  nerve  are  surrounded  by  loose  fatty  tissue,  continuous 
above  with  that  underlying  the  biceps,  and  below  with  that 
between  the  superficial  and  deep  muscles  of  the  forearm.  On 
the  outer  side  of  the  biceps  tendon,  at  the  junction  of  the  outer 
and  middle  third  of  the  elbow,  lies  the  musculo-spiral  nerve, 
dividing  into  radial  and  posterior  interosseous  branches,  and 
the  radial  recurrent  artery,  anastomosing  with  the  termina- 
tion of  the  superior  profunda.  The  brachial  artery  may  be 
compressed  by  forced  flexion  of  the  elbow- joint,  and  aneurisms 
in  this  position  have  been  treated  by  such  flexion.  In  extreme 


4o8 


SURGICAL  ANATOMY 


extension  also  the  vessel  becomes  flattened  and  compressed, 
and  it  has  been  ruptured  by  forcible  extension  applied  to  a 
flexed  and  injured  elbow. 

The  SKIN  OVER  THE  BACK  OF  THE  ELBOW  is  thicker  than  in 
front,  and  slightly  corrugated,  or  even  scaly.  It  possesses 
great  freedom  of  movement,  and  presents  a  bursa  over  the 
posterior  aspect  of  the  olecranon,  which  is  frequently  affected 
by  bursitis  from  pressure,  constituting  student's  or  miner's 
elbow.  Subcutaneous  bursting  of  the  bursa  may  set  up 
diffuse  cellulitis.  The  ulnar  nerve  is  frequently  injured  at 
the  elbow  on  account  of  its  exposed  position,  but  it  is 


FIG.  52.— OUTLINE  DIAGRAM  OF  TRANSVERSE  SECTION  OF  ELBOW. 
(After  Braune.) 


1.  Pronator  teres. 

2.  Flex,  carpi  rad. 

3.  Brach.  ant. 

4.  Supinator  longus. 

5.  Ext.  carpi  rad.  long. 


6.  Brachial  vessels . 

7.  Biceps  tendon. 

8.  Radial  nerve. 

9.  Anconeus. 
10.   Bursa. 


11.  Ulnar  nerve. 

12.  Median  nerve. 

13.  Triceps  tendon. 

14.  Int.  lat.  ligt. 

15.  Ext.  lat.  ligt. 


occasionally  covered  by  an  accessory  muscle,  the  epitrochleo- 
anconeus.  Sometimes  the  nerve  passes  in  front  of  the 
internal  condyle. 

The  ELBOW-JOINT  is  a  perfect  example  of  a  hinge,  and 
depends  for  its  strength  chiefly  upon  the  coaptation  of  the 
bony  surfaces. 

The  LOWER  END  OF  THE  HUMERUS,  flattened  from  side  to 
side  and  curved  with  the  convexity  forwards,  presents  at  the 
junction  of  the  shaft  and  articular  extremity,  and  above  the 
trochlea,  two  fossae — one,  the  anterior  and  smaller,  named  the 
coronoid :  the  other  posterior  and  larger,  the  olecranon  fossa. 
These  fossa-  contain  a  small  quantity  of  fatty  tissue,  separated 


UPPER  EXTREMITY  409 

from  the  bone  by  sacs  of  the  sy  no  vial  membrane,  and  receive  the 
extremities  of  coronoid  and  olecranon  processes  in  full  flexion 
and  extension  respectively.  The  bone  separating  these  fossae 
is  extremely  thin,  and  is  sometimes  perforated.  The  articular 
surface  proper  consists  of  capitellum  externally  and  trochlea 
internally.  The  former,  limited  to  the  anterior  aspect  of  the 
bone,  is  almost  hemispherical,  is  covered  by  articular  cartilage, 
and  presents  above  a  shallow  depression,  the  radial  fossa, 
which  receives  the  rim  of  the  radial  head  in  full  flexion. 
The  latter  is  separated  from  the  capitellum  by  a  shallow 
groove,  and  presents  a  surface  marked  by  a  deep  rounded 
depression,  which  winds  spirally  round  the  lower  end  of  the 
humerus  from  behind,  down,  forwards,  and  inwards.  Further, 
its  plane  is  not  at  right  angles  to  the  shaft,  but  slopes  down 
and  inwards. 

The  UPPER  END  OF  THE  RADIUS  articulates  with  the  capi- 
tellum by  a  concave  depression  on  the  head,  contact  being 
greatest  in  semiflexion  and  least  on  extension.  The  head  as 
a  whole  is  circular  in  outline,  and  articulates  with  the  lesser 
sigmoid  notch  of  the  ulna,  to  which  it  is  held  by  the  orbicular 
ligament.  The  head  is  connected  to  the  shaft  by  the  slightly 
constricted  neck. 

The  UPPER  END  OF  THE  ULNA  articulates  with  the  humerus 
by  the  great  sigmoid  cavity,  to  which  its  surface  is  adapted, 
presenting  a  median  longitudinal  rounded  crest,  which  divides 
the  surface  into  an  inner  portion  slightly  concave  transversely, 
and  an  outer  slightly  convex  transversely.  The  sigmoid  cavity 
as  a  whole  is  roughly  hemispherical,  and  has  been  likened 
to  the  Greek  letter  w,  owing  to  its  frequently  presenting  a  slight 
transverse  ridge  at  the  junction  of  the  olecranon  process 
above  with  the  coronoid  process  below.  The  olecranon 
process  is  widest  above,  but  constricted  below,  while  the 
coronoid  process  presents  on  its  outer  surface  the  lesser  sigmoid 
cavity  by  which  it  articulates  with  the  radial  head.  The 
ligaments  of  the  elbow-joint,  consisting  of  anterior,  posterior, 
and  lateral,  form  a  complete  capsule  for  the  joint.  The 
anterior  ligament  is  thin,  and  is  attached  to  the  humerus 
in  a  curved  line,  including  the  coronoid  and  radial  fossae,  and 
extending  thence  toward  the  condyles,  while  below  it  is 
attached  to  the  anterior  margin  of  the  coronoid  process, 
the  orbicular  ligament,  and  the  neck  of  the  radius.  It 


4io  SURGICAL  ANATOMY 

provides  origin  for  some  fibres  of  the  brachialis  anticus.  The 
posterior  ligament  is  the  weakest,  attached  above  to  the 
humerus,  enclosing  the  olecranon  fossa,  and  below  to  the 
superior  and  external  aspects  of  the  olecranon,  the  orbicular 
ligament,  and  neck  of  the  radius.  The  subanconeus  portion 
of  the  triceps  is  attached  to  it.  The  internal  lateral  ligament 
is  the  strongest,  and  is  triangular  in  outline,  the  apex  being 
attached  to  the  antero-inferior  aspect  of  the  internal  condyle, 
while  the  base  is  attached  anteriorly  to  the  inner  border 
of  the  coronoid,  and  posteriorly  to  the  inner  border  of  the 
olecranon,  and  to  the  bony  ridge  between  these  points.  The 
external  lateral  ligament  extends  from  the  external  condyle 
to  the  orbicular  ligament  and  neck  of  the  radius.  Accu- 
mulations of  fluid  in  the  elbow-joint  show  most  readily  through 
the  weak  anterior  and  posterior  ligaments.  Flexion  of  the 
joint  is  chiefly  prevented  by  contact  of  the  soft  parts,  while 
overextension  is  prevented  at  first  by  the  muscles  and  liga- 
ments, and  not  by  osseous  contact,  and  in  overextension, 
and  particularly  in  lateral  movements,  the  internal  lateral 
ligament  generally  surfers  most. 

The  superior  radio-ulnar  joint,  together  with  the  inferior, 
permits  of  the  movements  of  pronation  and  supination.  It 
consists  of  the  articulation  between  the  lesser  sigmoid  cavity 
of  the  ulna  and  radial  head,  together  with  the  ORBICULAR 
LIGAMENT.  The  latter  is  attached  anteriorly  and  posteriorly 
to  the  lesser  sigmoid  cavity,  forms  four-fifths  of  a  circle,  and 
is  cupped  superiorly  for  the  neck  of  the  radius.  A  common 
SYNOVIAL  MEMBRANE  lines  both  elbow  and  superior  radio-ulnar 
articulations.  Superiorly  the  membrane  dips  into  both 
olecranon  and  coronoid  fossae,  and  inferiorly  it  surrounds  the 
upper  part  of  the  neck  of  the  radius.  The  elbow-joint  is  a 
frequent  seat  of  tubercular  disease,  swelling  frequently  first 
appearing  round  the  margins  of  the  olecranon,  and  pointing 
sometimes  ultimately  in  the  same  region.  The  limb  tends  to 
become  semiflexed,  as  this  is  its  position  of  greatest  capacity, 
while  the  musculo  -  spiral  and  musculo  -  cutaneous  nerves, 
which  supply  both  the  joint  itself  and  some  muscles  controlling 
its  movements,  may  tend  by  reflex  irritation  to  produce 
muscular  rigidity.  The  ulnar  nerve  may  be  pressed  on  and 
produce  pain,  referred  to  the  little  finger  and  inner  side  of 
ring  finger.  Although  the  whole  head  of  the  radius  is  sur- 


UPPER  EXTREMITY 


411 


rounded  by  the  same  synovial  membrane,  it  generally  escapes 
infection  at  least  until  a  late  stage.  Practically  the  whole 
lower  humeral  epiphysis  is  within  the  joint,  but  only  a  portion 
of  the  upper  epiphysis  of  the  ulna. 

In  such  cases,  excision  of  the  elbow  is  performed  through 
a  vertical  posterior  incision,  extending  above  and  over  the 
olecranon.  The  incision  is  made  down  to  the  bone,  the  soft 
parts  are  shelled  to  either  side  by  a  periosteal  elevator,  the 


FIG.  53. —  LONGITUDINAL  SECTION  OF  ELBOW. 
(After  Braune.) 


1.  Triceps. 

2.  Brach.  ant. 

3.  Biceps. 

4.  Ext.  carp.  uln. 

5.  Flex,  profund.  dig. 


6.  Sup.  brev. 

7.  Sup.  longus. 

8.  Ext.  carp.  rad.  long. 

9.  Radial  nerve. 


10.  Median  cephalic  vein. 

11.  Humerus. 

12.  Ulna. 

13.  Radius. 


olecranon  is  cut  off  at  its  base,  and  the  joint  freely  opened, 
examined,  and  the  diseased  parts  removed.  The  head  of  the 
radius  can  generally  be  left  intact,  but  it  is  desirable  to 
remove  the  whole  lower  epiphysis  of  the  humerus,  cutting 
through  the  line  of  the  coronoid  and  olecranon  fossae.  In 
this  way  no  external  soft  parts  are  cut,  the  muscles  retain  their 
attachment  to  the  triceps  aponeurosis,  which  has  only  been 
split,  and  excellent  movement  is  obtained,  pronation  and 
supination,  flexion  and  extension,  being  generally  perfect. 


4i2  SURGICAL  ANATOMY 

Fractures  of  the  lower  end  of  the  humerus  have  already  been 
dealt  with  (see  p.  401). 

The  OLECRANON  PROCESS  is  generally  fractured  by  direct 
violence,  the  fracture  occurring  through  the  constricted  neck. 
As  a  rule,  displacement  is  slight,  owing  to  the  dense  triceps 
aponeurosis,  but  the  joint  is  often  involved  from  fracture, 
extending  through  the  articular  cartilage.  In  such  cases  it 
is  generally  best  to  cut  down  and  wire  the  fragments.  A 
small  epiphysis  at  the  apex  of  the  olecranon,  which  joins  the 
body  about  the  seventeenth  year,  has  occasionally  been 
separated,  considerable  displacement  resulting.  Fracture  of 
the  coronoid  is  very  rare.  Fracture  of  the  radial  head  is  rare, 
save  in  severe  injury,  and  is  generally  associated  with  disloca- 
tion. The  upper  epiphysis  of  the  radius  joins  the  shaft  at 
seventeen,  and  is  very  rarely  separated,  being  within  the 
orbicular  ligament. 

Dislocations  of  the  Elbow. — The  most  common  form  of 
dislocation  at  the  elbow  is  one  of  BOTH  BONES  BACKWARDS. 
The  bones  generally  go  together,  owing  to  the  firm  connection 
between  them.  They  tend  to  be  displaced  back  or  forwards 
rather  than  laterally,  owing  to  the  weakness  of  the  capsule, 
slight  muscular  support  antero-posteriorly,  and  to  the  narrow- 
ness of  the  articular  surface  in  that  direction,  while  a  forward 
displacement  is  rendered  almost  impossible  by  the  large 
curved  olecranon,  the  coronoid  process  rendering  much  less 
resistance  to  a  backward  displacement.  The  cause  is  gener- 
ally a  fall  on  the  hand  with  the  arm  fully  extended,  the  force 
producing  first  a  hyperextension,  which  brings  the  olecranon 
into  contact  with  the  humerus,  so  as  to  act  as  a  fulcrum,  and 
lever  the  coronoid  process  away  from  the  humerus.  The  upward 
acting  force  then  comes  into  play,  pushing  the  twro  bones  up 
behind  the  humerus.  Dislocation  may  also  be  produced  by 
wrenching  inwards  of  the  forearm  with  the  elbow  seminexed. 
The  internal  lateral  ligament  is  torn,  and  the  coronoid  turned 
down  under  the  articular  surface  of  the  humerus.  When  the 
dislocation  is  complete,  the  coronoid  is  opposite  to,  but  not 
in,  the  olecranon  fossae  ;  the  head  of  the  radius  lies  behind  the 
outer  condyle  ;  the  anterior  and  lateral  ligaments  are  torn  ; 
the  brachialis  anticus  much  stretched  and  generally  torn  ; 
the  anconeus  rendered  very  tense,  as  are  likewise  the  ulnar 
and  median  nerves  ;  and  the  biceps  is  markedly  stretched  over 


UPPER  EXTREMITY  413 

the  lower  end  of  the  humerus.  In  such  cases  the  tip  of  the 
olecranpn  lies  above  the  intercondylar  line,  notwithstanding 
the  flexion  of  the  limb,  which  generally  coexists,  while  the 
head  of  the  radius  can  generally  be  detected  posteriorly 
behind  the  external  condyle,  and  the  rounded  extremity  of  the 
humerus  felt  anteriorly.  Even  in  the  not  infrequent  incom- 
plete dislocation  of  both  bones  backwards,  the  relationship 
of  the  olecranon  to  the  condyles  is  a  good  guide  to  the  con- 
dition. 

LATERAL  DISPLACEMENTS  OF  BOTH  BONES  are  much  less 
common,  are  generally  incomplete,  and  are  more  frequently 
outwards  than  inwards,  owing  to  the  marked  projection  down- 
wards of  the  humeral  articular  surface  on  the  inner  side. 
A  slight  lateral  deviation  frequently  accompanies  the  back- 
ward displacement.  Dislocation  of  both  bones  forwards  is 
very  rare.  When  a  single  bone  is  dislocated,  it  is  generally  the 
RADIUS  which  is  affected,  owing  to  its  slight  connection  to  the 
humerus,  its  greater  mobility,  and  its  greater  connection  with 
the  hand.  It  is  most  often  DISPLACED  FORWARD  by  jerks  of 
the  forearm,  the  anterior  ligament  of  the  elbow-joint  and  the 
orbicular  ligament  giving  way.  The  radial  head  then  lies 
in  front  of  the  external  condyle,  producing  an  abnormal 
fulness,  and  flexion  and  supination  are  both  interfered  with. 

A  SPRAIN  OF  THE  ELBOW,  or  '  pulled  elbow,'  is  a  somewhat 
similar  condition  frequently  met  with  in  young  children, 
where,  owing  to  a  sudden  jerk  of  the  arm,  the  radius  is  pulled 
out  of  the  orbicular  socket.  The  limb  then  lies  in  a  position 
of  slight  flexion  and  pronation,  and  supination  is  impossible. 
The  radius  may  also  be  displaced  backwards  or  outwards. 
When  the  ULNA  is  dislocated  alone,  it  is  always  backwards. 
The  condition  is  very  rare. 

THE  FOREARM — SURFACE  ANATOMY.— The  forearm,  when 
well  developed,  is  oval  in  section  in  the  upper  third,  but 
slightly  flattened  anteriorly,  and  more  convex  posteriorly. 
In  the  middle  third  it  is  more  nearly  circular,  while  near  the 
wrist  it  becomes  flattened  antero-posteriorly.  In  women  and 
children,  however,  the  limb  is  rounded.  The  course  of  the 
radial  artery  is  represented  by  a  line  from  the  middle  of  the 
bend  of  the  elbow  to  the  styloid  process  of  the  radius.  Where 
the  limb  is  well  developed,  a  shallow  sulcus  follows  this  course, 
which  indicates  the  separation  between  the  radial  extensors 


414  SURGICAL  ANATOMY 

and  supinator  longus  on  the  outer  side,  and  the  flexors  and 
pronator  radii  teres  on  the  inner.  The  radial  pulse  is  easily 
felt  at  the  lower  part  of  this  sulcus,  the  vessel  lying  on  the 
radius  between  the  styloid  process  and  the  tendon  of  the 
flexor  carpi  radialis.  The  course  of  the  ulnar  artery  in  its  lower 
third  is  represented  by  a  line  from  the  internal  condyle  to 
the  radial  side  of  the  pisiform.  The  upper  third  curves  up 
and  outwards  to  meet  the  radial  at  the  middle  of  the  bend  of 
the  elbow. 

The  posterior  surface  is  narrower  than  the  anterior,  and 
is  limited  internally  by  the  ridge  of  the  ulna,  which  is  sub- 
cutaneous from  the  olecranon  to  the  styloid,  and  ex- 
ternally by  the  radius,  which  is  superficial  in  its  lower 
half,  but  is  obscured  by  muscles  in  the  upper  half.  A  sulcus, 
however,  frequently  exists,  which  indicates  the  position  of 
the  radius,  and  separates  the  supinator  longus  and  radial 
extensors  from  the  extensor  communis  digitorum.  The 
extensor  muscles  of  the  thumb  form  a  slight  projection  as 
they  cross  the  lower  end  of  the  radius. 

The  SKIN  on  the  front  of  the  forearm  is  thin,  delicate,  and 
sufficiently  transparent  to  exhibit  the  underlying  veins,  while 
on  the  posterior  aspect  it  is  thicker  and  covered  with  short 
hairs.  The  SUBCUTANEOUS  TISSUE  is  continuous  with  that 
of  the  arm,  contains  a  varying  amount  of  fat,  and  is  traversed 
by  the  superficial  veins,  lymphatics,  and  sensory  nerves. 
The  chief  VEINS  are  the  radial,  median,  and  anterior  and 
posterior  ulnar,  and  the  LYMPHATIC  VESSELS  accompany  them. 
The  internal  cutaneous  NERVE  supplies  the  ulnar  border  both  in 
front  and  behind  ;  the  musculo-cutaneous  supplies  the  radial 
border  both  anteriorly  and  posteriorly,  but  is  assisted  pos- 
teriorly by  a  branch  of  the  musculo-spiral.  The  DEEP  FASCIA 
is  directly  continuous  with  that  of  the  arm  and  hand,  and  forms 
a  complete  investment  for  the  limb.  In  front  it  receives  the 
bicipital  fascia,  and  behind  is  reinforced  by  the  triceps  aponeu- 
rosis.  It  is  attached  above  to  the  olecranon  process  and  con- 
dyles  of  the  humerus  ;  at  the  wrist  it  is  continuous  with  the 
anterior  and  posterior  annular  ligaments  ;  and  by  its  deep 
surface  it  gives  attachment  to  several  muscles,  and  sends  in 
intermuscular  septa,  which  are  attached  to  the  bones. 

The  MUSCLES  consist  of  anterior,  antero-external,  and  pos- 
terior groups.  The  anterior  group  arises  from  the  internal  con- 


UPPER  EXTREMITY  41  5 

dyle,  and  consists  of  a  superficial  and  a  deep  set.  The  superficial 
muscles,  from  without  inwards,  are  the  pronator  radii  teres, 
flexor  £arpi  radialis,  palmaris  longus,  flexor  sublimis  digitorum, 
and  flexor  carpi  ulnaris.  The  deep  set  consists  of  the  flexor 
profundus  digitorum,  flexor  longus  pollicis,  and  pronator 
quadratus  (which  rises  from  the  lower  quarter  of  the  anterior 
surface  of  the  ulna).  These  muscles  are  supplied  by  the 
median  and  its  anterior  interosseous  branch,  except  the  flexor 
carpi  ulnaris  and  inner  half  of  the  flexor  profundus  digitorum. 
The  antero-external  set  arise  from  the  external  condyle  and 
supracondylar  ridge,  and  include  the  supinator  longus,  the 
long  and  short  radial  extensors  of  the  carpus,  and  supinator 
brevis.  The  two  former  are  supplied  by  the  musculo-spiral, 
and  the  two  latter  by  its  posterior  interosseous  branch.  The 
posterior  muscles  consist  of  superficial  and  deep  sets.  The 
former  comprise  the  extensor  communis  digitorum,  extensor 
minimi  digiti,  extensor  carpi  ulnaris,  and  anconeus ;  the 
latter  the  extensor  ossis  metacarpi  pollicis,  extensores  brevis 
and  longus  pollicis,  and  extensor  indicis.  All  these  muscles 
are  supplied  by  the  posterior  interosseous  branch  of  the 
musculo  -  spiral,  except  the  anconeus,  which  is  supplied  by 
a  special  branch  of  the  musculo-spiral. 

The  MEDIAN  NERVE  passes  between  the  two  heads  of  the 
pronator  teres,  and  compression  between  these  may  explain 
occasional  cramp  of  the  flexor  muscles  after  violent  exercise. 
It  then  runs  down  the  centre  of  the  limb  between  the  super- 
ficial and  deep  muscles.  The  ULNAR  NERVE  enters  the  limb 
between  the  two  heads  of  the  flexor  carpi  ulnaris,  and  runs 
directly  from  the  internal  condyle  of  the  humerus  to  the  radial 
side  of  the  pisiform  bone. 

The  ULNAR  ARTERY  is  the  larger  of  the  brachial 
terminal  branches.  Its  line  has  already  been  given.  It 
lies  at  first  deeply  under  the  superficial  muscles  on  the 
flexor  profundus,  and  is  crossed  by  the  median  nerve,  the 
deep  head  of  the  pronator  teres  intervening.  It  is  accom- 
panied by  venae  comites,  and  continues  to  lie  on  the  flexor 
profundus,  but  becomes  more  superficial,  the  flexor  sublimis 
lying  to  its  outer,  and  the  flexor  carpi  ulnaris  and  ulnar  nerve 
to  its  inner  side.  It  gives  off  anterior  and  posterior  ulnar 
recurrents  to  the  anastomosis  at  the  elbow;  the  common 
interosseous,  and  the  anterior  and  posterior  ulnar  carpals. 


416  SURGICAL  ANATOMY 

The  common  interosseous  arises  close  to  the  origin  of  the  ulnar, 
and  divides  into  anterior  and  posterior  interosseous  arteries, 
the  former,  accompanied  by  venae  comites  and  the  anterior 
interosseous  nerve  (median),  lying  in  front  of  the  interosseous 
membrane,  between  the  flexor  profundus  and  flexor  longus 
pollicis,  and  supplying  the  nutrient  vessels  to  ulna  and  radius. 
At  the  upper  border  of  the  pronator  quadratus  it  passes  to  the 
posterior  surface,  and  joins  the  anastomosis  at  the  wrist. 
The  posterior  interosseous  passes  to  the  posterior  surface, 
between  the  upper  border  of  the  interosseous  membrane  and 
the  oblique  ligament,  and  soon  runs  between  the  superficial 
and  deep  muscles,  to  finally  anastomose  with  the  anterior 
interosseous.  It  gives  off  the  interosseous  recurrent  to  the 
elbow  anastomosis. 

The  course  of  the  RADIAL  ARTERY  has  also  been  given. 
The  supinator  longus  lies  to  its  outer  side,  and  at  first 
overlaps  it ;  the  pronator  teres  above  and  the  flexor  carpi 
radialis  below  lie  to  its  inner  side.  It  is  accompanied  by 
venae  comites,  and  the  radial  nerve  lies  to  its  outer  side  in 
the  middle  of  the  forearm.  It  gives  off  the  radial  recurrent, 
anterior  radial  carpal,  and  superficial  volar.  The  anasto- 
mosis between  the  vessels  in  the  forearm  is  very  free,  necessi- 
tating ligature  of  both  ends  of  a  divided  vessel. 

The  ulnar  may  be  LIGATURED  by  a  2-inch  incision  in  line  of 
the  artery  at  the  junction  of  the  upper  and  middle  third  of  the 
forearm,  the  interval  between  the  flexor  carpi  ulnaris  and 
flexor  sublimis  sought,  and  the  vessel  exposed.  At  the  wrist  a 
small  vertical  incision  in  the  line  of  the  artery,  commencing 
i  inch  above  the  wrist,  is  made  through  superficial  tissues, 
the  interval  between  flexor  carpi  ulnaris  and  flexor  sublimis 
sought,  and  the  vessel  ligatured.  The  radial  is  more  easily 
ligatured  at  any  part  of  its  course,  owing  to  its  more  super- 
ficial position.  An  incision  is  made  in  the  line  of  the  artery, 
the  supinator  longus  separated  from  the  pronator  radii  teres 
above,  or  the  flexor  carpi  radialis  below,  and  the  vessel  ex- 
posed and  ligatured.  Both  radial  and  ulnar  arteries  occasion- 
ally lie  immediately  beneath  the  skin. 

The  radius  and  ulna  lie  nearer  the  posterior  than  anterior 
surface  of  the  forearm,  particularly  in  the  upper  third.  Here, 
also,  the  muscles  lie  chiefly  in  front  and  on  either  side,  whereas 
lower  down  the  muscles  lie  chiefly  in  front  and  behind. 


UPPER  EXTREMITY  417 

In  compound  fractures,  therefore,  the  tendency  is  for  the 
fragments  to  project  on  the  posterior  surface.  While  the 
ulna  is  wide  above,  and  forms  the  chief  constituent  of  the 
elbow-joint,  the  radius  is  wide  below,  and  has  a  similar 
relation  to  the  wrist.  In  the  centre  of  the  arm  they  are  of 
about  equal  size.  The  INTEROSSEOUS  MEMBRANE  extends 
from  i  inch  below  the  tuberosity  of  the  radius  to  the  inferior 
radio-ulnar  articulation.  Its  fibres  run  generally  down  and 


FIG.  54.— LONGITUDINAL  SECTION  OF  FOREARM  AND  HAND. 
(After  Braune.) 

1.  Ext.  oss.  metacarp.  poll.  5.  Flex,  sublim.  dig.  9.  Ant.  annular  ligt. 

2.  Ext.  prim,  internal  polU  6.  Semilunar.  10.  Ext.  comm.  dig. 

3.  Flex.  long.  poll.  7.  Os.  magnum.  n.  Adduct.  poll. 

4.  Flex,  profund.  dig.  8.  Third  metacarp. 

inwards,  and  it  is  thicker  below  than  above.  It  helps  to 
communicate  shocks  received  by  the  hand  to  the  ulna,  and 
thus  prevent  upward  displacement  of  the  radius.  The 
oblique  ligament  connects  the  bones  above  the  interosseous 
membrane,  running  from  the  outer  border  of  the  coronoid  of 
the  ulna  down  and  out  to  the  lower  part  of  the  bicipital 
tuberosity  of  the  radius.  It  prevents  the  radius  being  driven 
away  from  the  humerus.  The  posterior  interosseous  artery 

27 


4i8 


SURGICAL  ANATOMY 


passes  between  the  oblique  ligament  and  the  interosseous 
membrane.  The  bones  lie  parallel  to  one  another  when  the 
limb  is  midway  between  pronation  and  supination,  and  the 
entire  interosseous  membrane  is  then  slack.  In  full  prona- 
tion the  interosseous  space  is  narrowest,  and  it  is  widest  in  full 
supination,  when  it  forms  an  irregular  ellipse. 

The  INFERIOR  RADIO-ULNAR  JOINT  consists  of  (a)  an  articula- 
tion between  the  head  of  the  ulna  and  the  sigmoid  facet  on 
the  lower  end  of  the  radius,  and  (b)  the  articulation  between 
the  head  of  the  ulna  and  the  triangular  fibro-cartilage  of  the 


16 


FIG.  55. — OUTLINE  DIAGRAM  OF  TRANSVERSE  SECTION  OF  FOREARM  IN 
LOWER  THIRD. 


(After  Braune.) 


i.  Flex,  sublimis 
2.  Flex,  profund. 
3.  Pronat.  quad. 
4.   Flex.  long.  poll. 
5.   Flex,  carpi  ulnar. 
6.  Ext.  indicis. 
7.  Ext.  long.  poll. 

8.  Ext.  comtn.  dig. 
9.  Ext.  brev.  poll. 
10.  Sup.  longus. 
n.  Radial  vessels. 
12.  Flex,  carpi  rad. 
13.  Median  nerve. 
14.  Palmaris  long. 

15.  Ulnar  vessels  and  nerve. 

16.  Ext.  carpi  ulnaris. 

17.  Ext.  min.  dig. 

1 8.  Ext.  carpi  rad.  brev. 

19.  Ext.  carpi  rad.  long. 

20.  Abductor  pollicis. 


wrist.  The  fibro-cartilage  is  attached  by  its  base  to  the 
inferior  border  of  the  radius,  and  by  its  apex  to  the  depres- 
sion at  the  base  of  the  styloid  of  the  ulna.  It  binds  the  bones 
together,  and  separates  the  inferior  radio-ulnar  joint  from  the 
wrist.  The  inferior  radio-ulnar  joint  presents  weak  anterior 
and  posterior  ligaments,  which  extend  from  either  side  of  the 
radial  sigmoid  notch  to  the  ulna  and  triangular  fibro-cartilage. 
The  synovial  membrane  is  loose,  and  lines  both  the  articulation 
between  radius  and  ulna  and  the  interspace  between  the  lower 
end  of  the  ulna  and  the  triangular  fibro-cartilage.  Pronation 


UPPER  EXTREMITY  419 

and  supination  movements  take  place  round  an  axis  from  the 
head  of  the  radius  through  the  end  of  the  ulna,  to  the  fourth 
metacarpal.  Pronation  is  limited  by  the  lower  two-thirds 
of  the  interosseous  membrane,  part  of  the  posterior  ligament 
of  the  wrist,  and  apposition  of  the  bones.  Supination  is 
limited  by  the  lower  third  of  the  interosseous  membrane,  the 
internal  lateral  ligament  of  the  wrist,  and  contact  of  the 
posterior  edge  of  the  sigmoid  cavity  of  the  radius  with  the 
tendon  of  the  extensor  carpi  ulnaris.  Supination  is  the 
more  powerful  movement  of  the  two. 

Fractures  of  the  Radius  and  Ulna. — BOTH  BONES  are  most 
frequently  fractured,  generally  as  a  result  of  direct  violence, 
both  bones  breaking  about  the  same  level,  in  the  middle  or 
lower  third.  f  Displacement  depends  chiefly  on  the  fracturing 
force,  and  may  be  in  almost  any  direction.  The  upper 
fragments  tend  to  be  flexed  by  the  biceps  and  brachialis 
anticus,  and  to  be  drawn  together  by  the  pronator  radii  teres, 
while  the  lower  are  drawn  together  by  the  pronator  quadratus, 
and  pulled  up  by  the  long  flexor  and  extensor  muscles.  Both 
pronators  tend  generally  to  slightly  pronate  the  radius.  If 
the  tendency  to  drawing  together  of  the  fragments  be  not 
corrected,  cross  union  may  result,  and  pronation  and  supina- 
tion movements  be  lost.  The  use  of  interosseous  pads  for 
correction,  however,  is  dangerous,  and  is  apt  to  cause  pain 
from  pressure  on  the  median  nerve,  and  swelling,  or  even 
gangrene,  from  pressure  on  the  vessels.  Fracture  of  the 
radius  alone  is  generally  caused  by  indirect  violence,  as  from 
falls  on  the  hand ;  that  of  the  ulna  alone  by  direct  violence, 
as  when  the  arm  is  raised  to  defend  a  blow.  When  the 
RADIUS  is  broken  above  the  insertion  of  the  pronator  radii  teres, 
the  upper  fragment  is  fully  supinated  by  the  supinator  brevis, 
and  flexed  by  the  biceps,  which  further  assists  the  supination. 
The  lower  fragment  is  drawn  toward  the  ulna,  and  pronated 
by  the  two  pronators.  As  the  upper  fragment  is  small,  the 
limb  is  generally  best  placed  in  flexion  and  full  supination  in 
treating  this  fracture.  When  the  fracture  occurs  below  the  in- 
sertion of  the  pronator  radii  teres,  the  upper  fragment  takes 
up  a  position  midway  between  pronation  and  supination,  the 
pronators  and  supinators  counteracting  one  another  ;  is 
flexed  by  the  biceps,  and  drawn  toward  the  ulna  by  the  pro- 
nator radii  teres.  The  lower  fragment  is  drawn  toward  the 

27 — 2 


420  SURGICAL  ANATOMY 

ulna,  and  pronated  by  the  pronator  quadratus,  while  the 
supinator  longus,  attached  to  the  styloid  of  the  ulna,  further 
tilts  the  upper  end  of  the  lower  fragment  toward  the  radius. 
Fracture  of  the  ULNA  alone  generally  occurs  in  the  lower 
segment  of  the  bone,  and  displacement  is  generally  slight. 

The  LOWER  END  OF  THE  RADIUS  is  a  favourite  seat  of  myeloid 
sarcoma,  which  is  sometimes  treated,  owing  to  its  compara- 
tively slight  malignancy,  by  removal  of  the  lower  portion  of 
the  bone.  This  is  perhaps  best  done  through  an  incision 
along  the  radial  sulcus.  The  lower  end  of  the  radius  is  the 
most  massive  part  of  the  bone,  is  quadrilateral,  and  curved 
forwards.  The  carpal  articular  surface  is  triangular  in  outline, 
and  is  inclined  down  and  forwards.  Its  outer  portion 
articulates  with  the  scaphoid,  and  the  inner  wjth  the  semi- 
lunar. 

Colles'  fracture  occurs  within  f  inch  of  the  lower  articular 
surface,  where  the  narrow  compact  shaft  meets  the  wide 
and  cancellous  extremity.  It  is  caused  by  indirect  violence, 
generally  from  falls  on  the  outstretched  palm,  and  the  displace- 
ment is  caused  by  the  fracturing  force.  Probably  at  the 
moment  of  impaction  the  forearm  forms  with  the  ground  an 
angle  of  less  than  60  degrees,  and  hence  the  force  is  borne 
by  the  lower  end  of  the  radius  alone,  which  is  broken  off  and 
driven  backwards.  Not  merely  is  the  lower  fragment  (a)  dis- 
placed backwards ;  it  is  also  (b)  rotated  backwards,  so  that 
the  articular  surface  looks  backwards  as  well  as  downwards. 
This  is  due  to  the  prominence  of  the  posterior  edge  of  the 
bone  receiving  an  undue  share  of  the  shock,  (c)  Further, 
the  lower  fragment  is  rotated,  so  that  it  looks  down  and  out- 
wards, instead  of  down  and  inwards,  owing  to  the  prominence 
of  the  radial  margin  of  the  bone  receiving  a  great  portion  of  the 
shock  from  the  thumb,  while  the  triangular  fibro-cartilage 
holds  the  ulnar  border  of  the  fragment  in  position.  Thus  the 
styloid  of  the  radius  comes  to  be  on  a  level  with,  or  even 
higher  than,  that  of  the  ulna,  and  the  hand  is  thrown  markedly 
to  the  radial  side.  Partial  impaction  generally  occurs,  the 
upper  fragment  being  driven  into  the  lower,  which  may  be 
splintered,  and  the  internal  lateral  ligament  of  the  wrist  is 
frequently  torn,  while  in  some  cases  the  ulnar  styloid  may  be 
broken  off.  When  the  angle  of  impact  is  over  60  degrees, 
the  force  generally  travels  up  the  bones  of  the  forearm,  and 


UPPER  EXTREMITY  421 

either  a  sprain  of  the  wrist  or  dislocation  of  the  elbow  occurs. 
In  on£  or  two  cases,  where  the  patient  fell  on  the  back  of  the 
hand,  the  position  of  the  fragments  has  been  reversed.  Some 
hold  that  the  displacement  is  due  to  muscular  action — 
supinator  longus,  extensors  of  thumb  and  radial  extensors — 
while  some  French  authorities  state  that  it  is  due  to  tearing 
of  the  bone  by  strain  on  the  wrist  ligaments.  The  epiphysis 
of  the  lower  end  of  the  radius,  which  includes  the  ulnar  facet 
and  insertion  of  the  supinator  longus,  joins  the  shaft  about 
the  twentieth  year,  and  is  occasionally  separated. 

Amputation  through  the  forearm  should  be  performed  as 
near  the  wrist  as  possible.  In  the  lower  part  a  circular, 
and  in  the  upper  part  a  modified  circular,  amputation, 
with  equal  antero-posterior  skin-flaps,  is  best.  After  re- 
tracting the  skin-flaps,  the  muscles,  vessels,  etc.,  are  divided 
circularly,  the  interosseous  membrane  cut,  and  the  bones 
sawn  across  at  the  same  level  after  reflection  of  the  perios- 
teum. The  periosteal  flaps  are  then  drawn  over  the  cut 
ends,  the  radial,  ulnar,  and  anterior  interosseous  vessels 
ligatured,  and  the  wound  stitched. 

THE  WRIST  AND  HAND— SURFACE  ANATOMY.— Like  the 
lower  portion  of  the  forearm,  the  wrist  is  compressed  antero- 
posteriorly,  and  presents  for  examination  anterior  and  pos- 
terior surfaces.  The  stylo  id  processes  of  radius  and  ulna  form 
prominent  landmarks,  separating  these  surfaces  from  one 
another,  the  styloid  of  the  radius  lying  anterior  to  and  \  inch 
below  that  of  the  ulna.  Three  furrows  can  frequently  be 
observed  on  the  anterior  skin  surface,  the  superior  corre- 
sponding to  the  level  of  the  styloid  of  the  ulna,  the  middle 
to  the  wrist-joint,  and  the  inferior  to  the  midcarpal  joint  and 
the  upper  border  of  the  anterior  annular  ligament.  From 
without  inwards  the  following  structures  are  met  with  at  the 
front  of  the  wrist :  First,  the  radial  artery,  which  is  accom- 
panied by  its  venae  comites,  and  by  the  superficial  volar  when 
that  vessel  is  given  off  high  up  ('  double  pulse  ')  ;  then  the 
tendon  of  the  flexor  carpi  radialis,  inserted  into  the  bases  of 
the  second  and  third  metacarpals,  followed  by  the  median 
nerve,  which  cannot  be  distinguished,  and  the  tendon  of  the 
palmaris  longus,  which  is  absent  in  10  per  cent,  of  cases,  and 
which,  when  present,  is  best  rendered  prominent  by  extending 
the  fingers  and  flexing  the  wrist,  and  either  closely  approxi- 


422  SURGICAL  ANATOMY 

mating  or  widely  separating  the  thenar  and  hypothenar 
eminences.  The  flexor  sublimis  digitorum  lies  immediately 
beneath  the  palmaris  longus.  Next  comes  the  ulnar  artery, 
with  its  venae  comites  ;  then  the  ulnar  nerve,  which  grooves 
the  radial  side  of  the  pisiform  bone  ;  and  then  the  flexor  carpi 
ulnaris,  which .  is  inserted  into  the  pisiform  bone,  and  is 
rendered  prominent  by  forcibly  flexing  the  little  finger  into 
the  palm,  and  slightly  flexing  the  wrist. 

On  the  dorsal  aspect,  commencing  externally  beyond  the 
radial  artery,  there  are  two  tendons  close  together,  the  first 
being  the  extensor  ossis,  and  the  second  the  extensor  primi 
internodii  pollicis,  separated  by  a  slit-like  interval.  About 
J  inch  farther  round  lies  the  tendon  of  the  extensor  secundi 
internodii  pollicis  (extensor  longus  pollicis).  These  tendons 
are  rendered  prominent  by  abducting  and  extending  the 
thumb.  Between  the  two  first  and  the  third  of  these  tendons 
lies  a  shallow  triangular  depression — the  TABATIERE  ANA- 
TOMIQUE — which  is  crossed  superficially  by  the  dorsal  vein 
of  the  thumb  (cephalic)  and  branches  of  the  radial  nerve,  and 
deeply  by  the  radial  artery  running  from  the  wrist  to  the 
posterior  extremity  of  the  first  interosseous  space.  The  floor 
of  the  area  is  formed  by  the  scaphoid,  trapezium,  and  base  of 
the  first  metacarpal  bone,  and  the  tendons  of  the  extensor 
carpi  radialis  longior  and  brevior  cross  the  base  of  the  triangle, 
to  be  inserted  into  the  bases  of  the  second  and  third  meta- 
carpal bones  respectively.  If  the  tendon  of  the  extensor 
longus  pollicis  be  followed  up  to  the  radius,  a  small  bony 
tubercle  is  met,  marking  the  outer  border  of  its  osseous  groove. 
Here  the  tendon  marks  the  centre  of  the  posterior  surface  of 
the  radius,  and  roughly  the  interval  between  the  scaphoid  and 
semilunar  bones.  Beyond  the  tendon  of  the  extensor  longus 
pollicis  comes  that  of  the  extensor  communis  digitorum. 
Further  to  the  ulnar  border  lies  the  tendon  of  the  extensor 
minimi  digiti,  which  can  be  felt  ;  then  comes  the  head  of  the 
ulna,  which  is  prominent  when  the  hand  is  pronated  ;  and, 
lastly,  there  is  the  tendon  of  the  extensor  carpi  ulnaris,  which 
is  inserted  into  the  base  of  the  fifth  metacarpal.  The  styloid 
process  of  the  ulna  becomes  most  distinct  on  supination,  lying 
to  the  ulnar  side  of  the  external  carpi  ulnaris  tendon.  Its  tip 
corresponds  to  the  line  of  the  wrist-joint. 

The  PALMAR  SURFACE  OF  THE  HAND  is  roughly  quadrilateral 


UPPER  EXTREMITY  41$ 

in  outline  and  concave  centrally,  where  the  skin  is  adherent 
to  the*  palmar  fascia.  This  central  depression  is  surrounded 
by  the  thenar  and  hypothenar  eminences.  At  the  upper 
extremity  of  the  thenar  eminence  is  a  bony  prominence,  due 
to  the  tubercle  of  the  scaphoid  and  ridge  of  the  trapezium, 
while  at  the  upper  extremity  of  the  hypothenar  eminence  is 
another  bony  prominence,  due  to  the  pisiform  bone,  with  the 
unciform  hook  below  it.  The  anterior  annular  ligament  takes 
attachment  from  these  points.  The  opponens  and  abductor 
pollicis  take  origin  from  the  ridge  of  the  trapezium,  and  the 
flexor  carpi  ulnaris  is  inserted  into  the  pisiform  and  hook  of 
the  unciform.  The  abductor  minimi  digiti  arises  from  the 
pisiform. 

Three  of  the  creases  traversing  the  palm  are  of  importance  : 
The  superior,  starting  from  a  point  about  i  inch  above  the 
base  of  the  index -finger,  curves  up  and  inwards,  and 
demarcates  the  thenar  eminence.  The  middle,  starting  from 
the  same  point,  crosses  the  palm  obliquely,  to  end  over  the 
hypothenar  eminence,  and  indicates  roughly  the  position  of 
the  superficial  palmar  arch,  whose  summit  almost  touches  it 
in  the  line  of  the  third  metacarpal.  The  deep  palmar  arch  is 
about  \  inch  nearer  the  wrist.  The  third  furrow  commences 
|  inch  above  the  base  of  the  little  finger,  and  runs  across 
toward  the  radial  border  of  the  palm,  indicating  the  upper 
limit  of  the  synovial  flexor  tendon  sheaths  of  the  three  outer 
fingers.  The  metacarpo-phalangeal  joints  lie  below  this  crease, 
and  |  inch  above  the  webs  of  the  fingers,  and  about  the  same 
level  the  palmar  fascia  divides  into  lour  slips  for  the  four 
fingers.  Between  these  slips  and  opposite  the  webs  of  the 
fingers  three  small  elevations,  corresponding  to  the  fatty  tissue 
between  the  fascia!"  slips,  may  .be  seen,  particularly  when  the 
first  phalanges  are  extended  and  the  other  two  are  flexed. 
The  transverse  creases  corresponding  to  the  metacarpo- 
phalangeal  joints  lie  f  inch  below  the  joints.  Those  at  the 
first  interphalangeal  joints  are  exactly  opposite  the  joints, 
while  those  at  the  second  interphalangeal  joints  are  a  little 
above  the  joints. 

The  superficial  PALMAR  ARCH  may  be  represented  by  a  curved 
line  running  from  the  pisiform  down  to  the  middle  crease  op- 
posite the  third  metacarpal,  and  then  up  to.  the  tubercle  of 
the  scaphoid  ;  while  the  deep  arch  may  be  represented  by  a 


424 


SURGICAL  ANATOMY 


Biceps  _ 

Musculo-spiral  nerve  - 
Brachio-radialis  _ 

Radial  nerve  - 

Radial  recurrent  artery .. 

Posterior  interosseous  nerve  . 

Ulnar  artery  _ 

Supinator  radii  brevis.. 

Radial  artery. _ 


Pronator  radii  teres 

Flexor  longus  pollicis 

Anterior  interosseous  nerve 


Brachio-radialis 


Superficial  volar  artery 

Extensor  ossis  metacarpi 

pollicis 


Opponens  pollicis    - 

Superficial  head  of  flexor  . 
brevis  pollicis 


Brachialis  anticus 
Median  nerve 
Brachial  artery 


Pronator  radii  teres 

Flexor  carpi  radialis 
Palmaris  longus 

Flexor  carpi  ulnaris 
Ulnar  nerve 

_  Ulnar  artery 


Flexor  profundus  digitorum 
Anterior  interosseous  artery 


.Pronator  quadratus 

--Median  nerve 
-  Abductor  pollicis 


-   Superficial  palmar  arch 


FIG.  56.— DEEP  DISSECTION  OF  FRONT  OF  RIGHT  FOREARM, 

AND  SUPERFICIAL  DISSECTION  OF  PALM. 

(From  Buchanan's  "Anatomy.") 


UPPER  EXTREMITY  425 

line  from  the  base  of  the  fifth  to  that  of  the  second  metacarpal, 
its  centre  corresponding  to  the  apex  of  the  hollow  of  the 
palm.  The  digital  arteries  bifurcate  about  J  inch  above  the 
webs  of  the  fingers. 

On  the  DORSAL  ASPECT  OF  THE  HAND  the  tendons  can 
generally  be  easily  made  out,  particularly  when  the  fingers 
are  hyperextended.  The  first  dorsal  interosseous  muscle  is 
chiefly  responsible  for  the  eminence  which  appears  when  the 
two  first  metacarpal  bones  are  firmly  approximated.  The 
prominence  of  the  knuckles  at  the  metacarpo-phalangeal  and 
interphalangeal  joints  is  formed  by  the  heads  of  the  proximal 
bones,  and,  therefore,  when  seeking  to  open  these  joints  when 
flexed,  the  knife  should  be  entered  distal  to  the  prominence. 

The  SKIN  OVER  THE  BACK  OF  THE  WRIST  AND  HAND  is  firmer 

than  that  of  the  palm,  and  freely  movable.  It  is  provided 
with  numerous  hairs  and  sweat-glands,  and  permits  of  the 
superficial  veins  being  seen  through  it.  Boils  and  furuncles 
not  infrequently  appear  on  this  surface  in  connection  with 
the  hair  or  glands,  but  do  not  occur  on  the  palm. 

The  SUBCUTANEOUS  TISSUES  are  very  lax,  permitting  great 
cedematous  swelling  and  accumulations  of  blood  or  pus.  The 
VENOUS  PLEXUS  forms  a  network  on  the  backs  of  the  fingers, 
which  collects  to  form  a  venous  arch  on  the  back  of  the  hand, 
with  the  convexity  pointing  downwards,  and  which  leads  to 
the  radial  vein  on  the  outer  side,  while  on  the  inner  side  it  is 
joined  by  a  vein  from  the  little  finger,  which  runs  in  the  fourth 
intermetacarpal  space  (vena  salvatella)  to  form  the  ulnar  veins. 
All  the  larger  veins  of  the  hand  are  on  the  dorsal  aspect,  and 
most  of  the  blood  of  the  hand  returns  dorsally.  The  LYM- 
PHATICS are  large,  and  widely  distributed  over  the  dorsum. 
The  NAILS  grow  about  ..\  inch  per  week,  and  are  frequently 
marked  by  transverse  grooves  in  illness  or  from  injury.  They 
are  also  said  to  be  altered  in  shape  by  some  diseases,  and  they 
share  in  clubbing  of  the  finger-tips,  which  occurs  in  certain  chest 
affections,  becoming  markedly  curved  (Hippocratic  hand) .  The 
matrix  of  the  nail  receives  a  large  branch  from  each  digital 
nerve,  and  is  extremely  sensitive  to  injury  or  inflammatory 
processes.  Such  inflammatory  conditions  affecting  the  matrix 
are  referred  to  as  onychia  (or  paronychia,  when  the  surround- 
ing parts  are  affected),  and  may  lead  to  deformity  or  destruc- 
tion of  the  nail,  a  new  nail  forming  if  the  matrix  survives. 


426  SURGICAL  ANATOMY 

The    SKIN    OF    THE    FRONT   OF    THE    WRIST   AND    HAND    varies 

much  in  character.  On  the  front  of  the  wrist  it  is  thin  and 
comparatively  movable,  but  is  connected  with  the  deep  fascia. 
The  superficial  VEINS  are  visible  through  it,  and  the  median 
vein  of  the  forearm  generally  takes  origin  about  this  position. 
The  skin  over  the  thenar  eminence  is  also  thin,  much  thicker 
over  the  hypothenar  eminence,  and  very  thick  over  the  palm, 
where,  in  addition,  it  is  firmly  bound  down  to  the  palmar 
fascia  by  numerous  fibrous  septa.  The  cuticle  is  thick,  and 
both  on  palm  and  fingers  presents  numerous  fine  ridges,  on 
which  open  large  numbers  of  sweat-glands  (2,800  per  square 
inch  on  the  palm).  The  papillce  of  the  fingers  are  richly 
supplied  with  Pacinian  corpuscles,  the  sensation  of  touch  being 
more  active  on  the  palmar  aspect  of  the  terminal  phalanx  of 
the  index-finger  than  on  any  other  part  of  the  body,  except 
the  tip  of  the  tongue.  The  dorsum,  on  the  other  hand,  is 
much  less  sensitive,  while  the  skin  of  the  middle  of  the  fore- 
arm and  of  the  shoulders  is  very  insensitive.  There  are  no 
hairs,  sebaceous  glands,  nor  large  superficial  veins,  and  few 
lymphatics  on  the  palmar  aspect. 

The  SUBCUTANEOUS  TISSUE  is  dense  and  scanty,  the  fat 
being  arranged  in  lobules  between  the  fibrous  septa.  It  is 
continuous  with  that  of  the  forearm  and  fingers,  and  with 
the  fatty  tissue  in  the  central  compartment  of  the  palm, 
between  the  slips  of  the  palmar  fascia.  It  is  also  continuous 
laterally  with  that  on  the  dorsum.  Over  the  proximal  and 
middle  phalanges  it  is  connected  with  the  fibrous  sheaths  of 
the  flexor  tendons,  while  on  the  distal  extremity  of  the 
terminal  phalanges  it  forms  the  pulp  of  the  finger,  which  is 
intersected  by  numerous  trabeculae  passing  from  the  skin  to 
the  periosteum  of  the  bone  (cutaneous  phalangeal  ligaments  of 
Cleland).  These  trabeculae  are  of  importance  in  suppurative 
affections  of  the  terminal  phalanges,  as  they  tend  to  direct  the 
process  downwards  from  the  surface  to  the  periosteum, 
whereby  .a  simple  whitlow  may  give  rise  to  a  subperiosteal 
abscess,  or  paronychia,  with  partial  necrosis  of  the  bone,  the 
epiphyseal  end,  to  which  the  flexor  profundus  is  attached, 
generally  surviving  (the  epiphysis  unites  about  the  twentieth 
year). 

The  PALMAR  FASCIA  is  strong  and  unyielding,  is  compara- 
tively free  from  vessels  and  nerves,  and  hence  renders  the 


UPPER  EXTREMITY  427 

overlying  skin  suitable  for  withstanding  pressure  and  friction. 
The  intimate  connection  between  skin  and  fascia  also  prevents 
gaping  of  wounds  and  accumulations  of  oedema  or  blood  ; 
indeed,  when  inflammation  does  occur  in  this  region,  it 
generally  produces  much  pain  from  tension  of  the  parts.  The 
palmar  fascia  consists  of  a  stout  central  palmar  portion,  and 
two  lateral  expansions  to  the  thenar  and  hypothenar  eminences, 
by  which  these  latter  are  enclosed.  The  central  portion  is 
connected  superficially  with  the  skin  by  numerous  septa,  but 
its  deep  surface,  lying  over  the  flexor  tendons,  is  smooth. 
Commencing  above  where  it  is  continuous  with  the  anterior 
annular  ligament  and  palmaris  longus  muscle,  it  widens  out 
as  it  approaches  the  fingers,  and  divides  opposite  the  heads 
of  the  four  inner  metacarpal  bones  into  four  slips,  which  pass 
to  the  roots  of  the  respective  fingers.  These  again  divide, 
and  pass  to  the  sheaths  of  the  flexor  tendons,  transverse  meta- 
carpal ligaments,  and  skin.  This  fascia  is  so  dense  that  sup- 
purative  processes  can  hardly  come  forward  through  it,  but 
are  generally  forced  down  along  the  fingers,  or  up  into  the 
forearm,  or  even  back  on  to  the  dorsum  of  the  hand. 

DUPUYTREN'S  CONTRACTION  of  the  palmar  fascia  most  fre- 
quently affects  the  slips  to  the  ring  and  little  fingers,  pro- 
ducing flexion  of  these  fingers  and  wrinkling  of  the  overlying 
skin  when  an  attempt  is  made  to  straighten  the  fingers.  The 
CENTRAL  COMPARTMENT  OF  THE  PALM  is  bounded  superficially 
by  the  palmar  fascia,  deeply  by  the  aponeurosis  of  the  in- 
terossei  muscles,  and  laterally,  both  at  the  thenar  and  hypo- 
thenar eminences,  by  the  fusion  of  these  two  layers.  Superiorly 
it  narrows,  and  is  continuous  with  the  wrist  under  the  anterior 
annular  ligament,  and  inferiorly  it  widens  out,  being  con- 
tinued along  the  fingers  by  the  flexor  tendon  sheaths,  while 
between  the  fingers  it  communicates  with  the  subcutaneous 
tissue  of  the  palm.  It  contains  the  superficial  and  deep 
tendons  in  their  synovial  sheaths,  and  the  lumbricales  muscles, 
the  superficial  palmar  arch  and  its  branches,  and  the  median 
nerve  and  its  terminal  branches.  Under  the  central  compart- 
ment is  a  DEEP  COMPARTMENT,  lying  between  the  aponeurosis 
of  the  interossei  muscles  and  the  bones,  which  contains  the 
interossei  muscles,  the  deep  palmar  arch,  and  the  deep  division 
of  the  ulnar  nerve. 

The    ANTERIOR   ANNULAR   LIGAMENT   is    attached   to    the 


428  SURGICAL  ANATOMY 

tubercle  of  the  scaphoid  and^ridge  of  the  trapezium  ex- 
ternally, and  internally  to  the  pisiform  and  hook  of  the 
unciform.  Above  it  is  continuous  with  the  fascia  of  the 
forearm,  and  below  with  the  palmar  fascia.  It  forms  a  tunnel 
with  the  carpal  bones  for  the  passage  of  the  flexor  tendons 
and  median  nerve  to  the  central  compartment  of  the  hand, 
and  gives  attachment  to  the  short  muscles  of  the  thumb  and 
little  finger.  The  tendon  of  the  palmaris  longus  expands  in 
front  of  it,  and  it  is  crossed  externally  by  the  superficial  volar 
branch  of  the  radial,  and  on  the  inside  by  the  ulnar  artery  and 
nerve. 

The  flexors  sublimis  and  profundus  digitorum  have  a 
COMMON  SYNOVIAL  SHEATH  (great  palmar  bursa),  which,  com- 
mencing fully  an  inch  above  the  annular  ligament,  extends 
down  under  it  for  about  the  same  distance,  and  then  sends 
short  prolongations  extending  to  the  centre  of  the  metacarpal 
bones  along  the  index,  middle,  and  ring  finger  tendons.  Beyond 
this  these  tendons  have  separate  sheaths  in  the  fingers,  which 
begin  at  the  necks  of  the  metacarpal  bones,  fully  J  inch 
above  the  terminations  of  the  others,  and  extend  to  the  bases 
of  the  terminal  phalanges.  The  sheath  to  the  little  finger, 
on  the  other  hand,  generally  goes  direct  to  the  base  of  the 
terminal  phalanx,  while  the  long  flexor  of  the  thumb  has  a 
separate  sheath  of  its  own,  which  commences  in  the  forearm 
J  inch  below  the  common  sheath,  and  extends  to  the  base  of 
the  terminal  phalanx.  Thus,  a  SEPTIC  WOUND  of  the  little 
finger  is  apt  to  produce  a  suppuration  of  the  common  synovial 
sheath,  which  might  extend  into  the  forearm,  and  cause  im- 
pairment of  movement  of  all  the  fingers.  A  septic  wound  of 
the  thumb  might  also  produce  a  lesion,  extending  up  the  fore- 
arm, but  would  only  probably  involve  the  thumb.  A  septic 
lesion  of  the  index,  middle,  or  ring  fingers  would  probably 
produce  a  local  condition,  as  these  fingers  have  each  a  separate 
distal  synovial  sheath,  which  only  extends  up  to  the  neck  of 
the  corresponding  metacarpal  bone,  and  does  not  communicate 
with  the  common  sheath.  Abscesses  in  these  sheaths  are 
sometimes  referred  to  as  thecal.  INCISIONS  for  relief  of  ab- 
scesses may  be  made  deeply  in  the  middle  line  of  the  terminal 
phalanges  ;  and  distal  to  the  palmar  arch,  over  the  metacarpal 
of  the  index  and  ring  fingers  particularly,  without  danger 
of  cutting  vessels.  The  sheath  of  the  common  flexor  tendon 


UPPER  EXTREMITY 


429 


is  not  infrequently  affected  by  chronic  tubercular  synovitis, 
extending  both  into  the  palm  and  up  into  the  forearm, 
necessitating  its  free  removal. 

The  tendons  of  the  FLEXOR  PROFUNDUS  are  inserted  into  the 
base  of  the  terminal  phalanges,  having  perforated  the  tendons 
of. the  FLEXOR  SUBLIMTS,  which  are  inserted  into  the  sides  of 
the  middle  phalanges.  The  tendons  and  their  sheaths  are 


FIG. 


57. — THE    GREAT    PALMAR    BURSA,    AND    THE    SYNOVIAL 
SHEA-THS  OF  THE  FLEXOR  TENDONS. 
(From  Buchanan's  "Anatomy.") 


1.  Anterior  annular  ligament. 

2.  Synovial  sheath  of  thumb. 


3.  Great  palmar  bursa. 

4.  Synovial  sheath  of  little  finger. 


enclosed  in  strong  FIBROUS  THECLE,  which  are  best  developed 
over  the  shafts  of  the  two  proximal  phalanges  of  each  finger, 
but  which  are  thin  over  the  joints,  pus  finding  its  way  here 
into  the  sheaths.  These  sheaths  gape  when  cut,  unless  care 
be  taken  to  close  them,  and  may  permit  access  of  septic 
matter.  The  tendons  lying  within  the  synovial  sheaths  are 
not  free,  but  are  attached  to  them  by  practically '  mesenteric  ' 
folds,  which  carry  the  nutrient  vessels  to  the  tendons.  Within 


430  SURGICAL  ANATOMY 

the  digital  sheaths  these  folds  are  replaced  by  the  ligamenta 
longa  and  brevia,  which  are  situated  near  the  insertions  of 
the  tendons.  Rupture  of  the  synovial  sheaths  may  destroy 
the  nutrient  vessels  of  a  portion  of  tendon,  and  is  generally 
followed  by  effusion.  As  the  synovial  sheaths  communicate 
freely  with  the  surrounding  lymphatics,  septic  absorption 
takes  place  rapidly  from  them. 

The  LUMBRICALES  arise  from  the  outer  edges  of  the  tendons 
of  the  deep  flexor,  and  are  inserted  into  the  fibrous  expansion 
of  the  extensor  tendons  of  the  four  fingers.  A  growth  on  the 
tendon  or  tendon  sheath  may  limit  the  movement  of  a  finger, 
preventing  extension,  and  contractions  of  the  finger  may  also 
result  from  contraction  of  the  sheath,  adhesion  of  the  tendon 
to  the  sheath,  or  contraction  of  the  muscles. 

The  ULNAR  ARTERY,  on  reaching  the  palm,  divides  into 
superficial  and  deep  branches,  the  former,  with  the  superficial 
volar  of  the  radial,  forming  the  SUPERFICIAL  ARCH,  which  lies 
in  the  central  compartment  of  the  hand,  and  gives  off  four 
digital  branches,  one  to  the  ulnar  border  of  the  little  finger, 
and  the  other  three  dividing  J  inch  above  the  webs  to  supply 
each  side  of  two  adjacent  fingers.  The  DEEP  BRANCH  of  the 
ulnar  sinks  between  the  abductor  and  short  flexor  of  the  little 
finger  to  form  the  DEEP  ARCH  with  the  termination  of  the  radial. 

The  RADIAL  ARTERY  passes  from  the  front  of  the  wrist  below 
the  styloid  process,  outwards  over  the  external  lateral  liga- 
ment of  the  wrist,  and  under  the  extensores  ossis  and  primi 
intern odii  pollicis,  to  enter  the  tabatiere,  whence  it  passes 
between  the  heads  of  the  first  dorsal  interosseous  muscle  to 
reach  the  palm.  It  gives  off  a  posterior  radial  carpal  to  form 
the  posterior  carpal  arch  with  the  posterior  ulnar  carpal  (from 
which  arise  the  second  and  third  dorsal  interosseous  arteries), 
the  first  dorsal  interosseous  artery,  the  dorsalis  indicis,  and 
dorsalis  pollicis.  As  the  artery  is  in  close  contact  with  the 
carpo-metacarpal  joint,  it  is  apt  to  be  wounded  in  amputation 
of  the  thumb  or  excision  of  the  first  metacarpal.  In  the  palm 
the  artery  forms  the  deep  palmar  arch  with  the  deep  branch 
of  the  ulnar,  and  gives  off  the  arteria  princeps  pollicis,  the 
radialis  indicis,  three  palmar  interossei,  two  or  three  recurrent 
branches  to  the  anterior  carpal  arch,  and  three  posterior 
perforating  branches  to  the  dorsal  interosseous.  The  deep 
arch  lies  in  the  deep  compartment  under  the  flexor  tendons 


UPPER  EXTREMITY  431 

and  interosseous  aponeurosis,  its  lower  border  corresponding 
to  the  upper  border  of  the  superficial.  The  ANASTOMOSIS 
between  the  various  vessels  of  the  hand  is  so  free  that  when  a 
vessel  is  cut  it  is  generally  necessary  to  ligature  both  ends. 
It  is  often  difficult  to  do  this  where  the  wound  is  of  the 
punctured  variety  ;  and  where  the  deep  palmar  arch  has  been 
wounded,  it  has  been  suggested  to  reach  it  from  the  dorsal 
aspect  of  the  hand  by  resecting  the  proximal  portion  of  the 
third  metacarpal  bone.  The  anterior  and  posterior  carpal 
arches  communicate  with  one  another,  with  the  interosseous 
vessels,  and  with  the  deep  palmar  arch  ;  while  the  two  palmar 
arches,  besides  being  in  direct  communication,  anastomose 
through  the  digital  branches  of  the  superficial  arch,  and  the 
palmar  interosseous  of  the  deep  arch,  which  form  a  rich  plexus 
in  the  pulp  of  the  fingers.  Pressure  applied  to  the  palm  for 
arrest  of  haemorrhage  may,  nevertheless,  lead  to  gangrene. 
The  LYMPHATICS  of  the  fingers  are  numerous  and  large,  and 
lymphangitis  frequently  follows  septic  wounds. 

The  POSTERIOR  ANNULAR  LIGAMENT  lies  higher  than  the 
anterior,  and  runs  obliquely  from  without  inwards.  It  consists 
of  a  thickening  of  the  deep  fascia,  and  is  attached  externally  to 
the  radius  and  internally  to  the  cuneiform  and  pisiform  bones 
and  palmar  fascia.  It  sends  in  processes  to  the  underlying 
bones  by  which  six  compartments  are  formed  for  (i)  extensores 
ossis  and  primi  internodii  pollicis ;  (2)  extensores  carpi 
radialis  longus  and  brevior  ;  (3)  extensor  longus  pollicis  ; 
(4)  extensor  indicis  and  communis  digitorum  ;  (5)  extensor 
minimi  digiti ;  (6)  extensor  carpi  ulnaris.  These  tendons 
lie  on  the  posterior  ligament  of  the  wrist-joint,  which  is  very 
thin,  and  frequently  permits  small  protrusions  of  synovial 
membrane  from  the  wrist-joint.  The  synovial  tendon 
sheaths  commence  slightly  above  the  annular  ligament,  while 
inferiorly  they  are  variously  described  either  extending  as 
shown  in  Fig.  58,  or  as  follows  :  Below,  all  the  sheaths 
extend  to  the  insertions  of  the  tendons,  except  (i),  which 
extends  to  the  first  carpo-metacarpal  joint,  and  (4)  and 
(5),  which  extend  to  the  middle  of  the  metacarpus.  As  these 
sheaths  are  injured  in  Colles'  fracture,  fixation  of  the  fingers 
is  apt  to  occur  (unless  prevented  by  passive  movement) 
from  adhesions  between  tendons  and  sheaths.  Ganglion  is  a 
cystic  protrusion  of  the  tendon  sheaths  of  the  back  of  the 


432 


SURGICAL  ANATOMY 


hand  or  of  the  carpus  which  may  be  treated  by  subcutaneous 
rupture  or  small  incision. 

The  WRIST-JOINT  consists  of  the  articulation  between 
radius  and  triangular  nbro-cartilage  above,  and  scaphoid, 
semilunar,  and  cuneiform  bones  below,  the  upper  or  radial 
surface  being  concave  from  side  to  side  and  from  before 


FIG.  58  —THE  SYNOVIAL  SHEATHS  OF  THE   EXTENSOR  TENDONS. 
(After  L.  Testut's  "  Anatomie  Humaine.") 


1.  Extensor  communis  digitorum. 

2.  Radial  carpal  extensors. 

3.  Extensor  brevis  pollicis. 

4.  Extensor  longus  pollicis. 


5.  Extensor  carpi  ulnaris. 

6.  Extensor  minimi  digiti. 

7.  Posterior  annular  ligament. 


backwards,  the  apex  of  the  curve  lying  J  inch  above  a  line 
joining  the  two  styloid  processes.  It  is  surrounded  by  a 
CAPSULAR  LIGAMENT,  which  is  described  as  consisting  of  a 
strong  anterior  ligament,  extending  from  the  lower  end  of  the 
radius,  triangular  nbro-cartilage,  and  ulnar  styloid  to  the  first 
and  second  rows  of  carpal  bones  ;  a  weak  posterior  ligament, 
extending  from  the  same  points  posteriorly  to  the  first  row 


UPPER  EXTREMITY 


433 


of  carpal  bones  ;  an  external  ligament,  extending  from  the 
radial  slyloid  to  the  tuberosity  of  the  scaphoid ;  and  an 
internal,  extending  from  the  ulnar  styloid  to  the  pisiform  and 
cuneiform  bones  and  annular  ligament. 

The  midearpal  articulation  roughly  conforms  in  outline 
to  the  wrist -joint,  and  possesses  a  capsular  ligament  and 
an  extensive  synovial  cavity.  In  it  the  scaphoid,  semilunar, 
and  cuneiform  articulate  with  the  trapezium,  trapezoid, 
os  magnum,  and  unciform.  There  are  FIVE  ARTICULAR 
SYNOVIAL  SACS  connected  with  the  carpus :  (i)  Radio- 


FIG.  59. — DIAGRAM  OF  THE  FIVE  SYNOVIAL  MEMBRANES  OF  THE  HAND. 


1.  Pisiform. 

2.  Unciform. 

3.  Os  magnum. 


4.  Trapezoid. 

5.  Trapezium. 

6.  Cuneiform. 


7.  Semilunar. 

8.  Scaphoid. 

9.  Triangular  fibro-cartilage. 


carpal  or  wrist ;  (2)"  midearpal,  which  extends  between  all 
the  bones  and  also  to  the  carpo-metacarpal  joints  of  the 
index  and  middle  fingers  ;  (3)  between  the  unciform  and  ring 
and  little  fingers — (2)  and  (3)  are  sometimes  continuous, 

(4)  between  the  trapezium  and  metacarpal  of  the  thumb  ; 

(5)  between   the   pisiform   and   cuneiform.     As  just   stated, 
the  metacarpal  bone  of  the  thumb  possesses  a  separate  articu- 
lation, while  these  of  the  first  two  fingers  always,  and  the  last 
two    fingers   sometimes,    communicate    with    the   midearpal 
joint.     The  wrist  depends  for  its  strength  chiefly  upon  the 
strong  tendons  surrounding  it,  and  is  protected  to  an  extent 

28 


434  SURGICAL  ANATOMY 

by  the  numerous  joints  of  the  hand,  which  lessen  shocks 
communicated  to  it,  and  which  also  prevent  leverage  of  the 
joint  from  the  distal  side.  It  is  stated  that  DISLOCATION 
of  the  wrist  is  extremely  rare,  but  it  should  be  borne  in  mind, 
when  estimating  its  frequency,  that  it  is  often  easily  reduced, 
a  slight  pull  of  the  hand  sufficing  in  some  cases.  The  dis- 
location of  the  wrist  backwards  is  much  more  common,  prob- 
ably owing  to  falls  on  the  outstretched  hand  being  the 
common  mode  of  production.  The  hand  is  generally  adducted 
to  the  ulnar  side,  whereas  in  Colles's  fracture  it  is  thrown  to 
the  radial  side.  The  movements  permitted  at  the  wrist-joint 
are  flexion,  extension,  abduction,  and  adduction,  and,  by  a 
combination  of  these,  circumduction.  The  midcarpal  joint 
also  participates  to  an  extent  in  these  movements.  Forced 
extension,  as  in  falls  on  the  palm,  is  a  more  frequent  source 
of  injury  to  the  wrist  than  forced  flexion.  In  forced  flexion 
of  the  hand  the  head  of  the  os  magnum  has  occasionally  been 
displaced  backwards,  so  as  to  project  on  the  dorsum  of  the 
wrist,  the  ligaments  being  torn.  The  condition  may  simulate 
ganglion  of  the  wrist.  The  carpus  is  frequently  affected  by 
tubercular  disease,  which,  owing  to  the  extensive  synovial 
sheath,  rapidly  spreads  to  the  various  bones  of  the  carpus, 
and  not  infrequently  to  the  carpo-metacarpal  joints.  The 
ligaments  of  the  joint  and  overlying  tendon  sheaths  also 
become  affected,  and  a  fusiform  swelling,  more  prominent 
posteriorly  than  anteriorly,  is  produced,  while  the  hand 
generally  remains  straight.  In  the  later  stages  the  forearm 
and  fingers  become  wasted  and  powerless,  while  sinuses  form, 
generally  posteriorly. 

EXCISION  OF  THE  WRIST  may  be  performed  in  various  ways, 
and  while  it  is  a  difficult  operation  on  the  normal  cadaver,  it 
is  comparatively  easy  in  the  diseased  condition.  A  vertical 
incision,  some  3  to  4  inches  long,  is  made  over  the  wrist  in  the 
line  of  the  common  extensor  tendon  to  the  index  finger,  that 
tendon  being  thrown  to  the  ulnar  side  prior  to  making  the 
incision  by  flexing  the  three  inner  fingers,  and  extending  the 
index,  when  it  is  drawn  aside  by  the  band  connecting  it  to  the 
tendon  of  the  middle  finger.  The  incision  is  extended  on  to 
the  lower  end  of  the  radius.  The  tendons  of  the  extensor 
secundi  internodii  pollicis  and  extensores  carpi  radialis  longior 
and  brevior  are  drawn  to  the  radial,  and  the  extensor  tendons 


UPPER  EXTREMITY  435 

of  the  fingers  drawn  to  the  ulnar  side,  the  joint  is  flexed,  and 
the  firs;t  row  of  bones  is  exposed  and  shelled  out  with  the 
periosteal  elevator,  and  then  the  carpo-metacarpal  joints  are 
opened,  and  the  second  or  lower  row  of  bones  removed. 
Wherever  possible  the  trapezium,  hook  of  the  unciform,  and 
pisiform  are  left  intact,  as  are  also  the  lower  end  of  the  radius 
and  ulna,  the  ends  of  the  metacarpal  bones,  and  also  the 
tendons  in  their  sheaths.  Excellent  results  are  obtained, 
even  the  more  delicate  movements  of  the  fingers,  such  as 
apposition  of  the  thumb  and  forefinger,  being  retained.  Ampu- 
tation at  the  wrist  for  extensive  crushing  or  tubercular  disease 


5  i^VJLLV^* 

f§^C5*Ss£&9^  . 

21 


FIG.  60. — TRANSVERSE  SECTION  OF  WRIST. 
(Bellamy  after  Henle  [Morris].) 

1.  First  metacarp.  8.  Palmaris  brev.  15.  Ext.  prim,  inter,   poll. 

2.  Trapezium.  9.  Ulnar  vessels  and  nerve.  16.   Radial  vessels. 

3.  Trapezoid.  10    Median  nerve.  17.   Ext.  carp.  rad.  long. 

4.  Os  magnum. 

5.  Unciform. 

6.  Ext.  carpi  ulnar. 

7.  Hypothenar  muscles. 


Flex,  sublim.  and  profund.  18.  Ext.  carp.  rad.  brev. 

Flex.  long.  poll.  19.  Ext.  indicis. 

Flex.  carp.  rad.  20.  Ext.  comm.  dig. 

Thenar  muscles.  21.  Ext.  min.  dig. 


of  the  carpus  is  rarely  performed.  An  elliptical  incision 
planned  to  give  a  good  palmar  flap,  beginning  at  the  carpo- 
metacarpal  joint  of  the  thumb,  arching  across  the  palm 
to  the  extent  of  2  inches  below  the  wrist,  and  then  turning 
up  again  to  the  pisiform,  is  made  on  the  palmar  surface,  and 
is  completed  dorsally  by  an  incision,  with  its  concavity  toward 
the  fingers,  and  extending  J  inch  above  the  wrist.  This 
incision  is  made  through  the  skin  and  superficial  tissues,  and 
includes  the  superficial  branches  of  the  radial  and  ulnar 
nerves.  The  tendons  are  then  cut,  commencing  at  the  radial 
side,  and  the  joint  is  also  opened  at  that  side,  so  as  to  avoid 

28—2 


436  SURGICAL  ANATOMY 

injury  to  the  triangular  nbro-cartilage  of  the  wrist.  Dorsally 
the  tendons  of  the  two  radial  extensors  and  extensores  ossis 
metacarpi  and  primi  internodii  pollicis,  together  with  ex- 
tensores indicis,  communis,  minimi  digiti,  and  carpi  ulnaris, 
radial  nerve,  dorsal  branch  of  the  ulnar  nerve,  and  radial  artery 
are  cut ;  while  in  the  palmar  wound  the  tendons  of  the  flexor 
sublimis,  profundus,  longus  pollicis,  carpi  radialis,  ulnar 
artery,  superficial  volar,  ulnar  and  median  nerves,  and  parts 
of  the  short  muscles  of  the  thumb  and  little  finger  are  cut. 

THE    THUMB    AND    FINGERS. —The    carpo-metacarpal 
joints   of   the   index,     middle,    and   ring     fingers   permit   of 
little  movement,   whereas  that  of  the  thumb  possesses  free 
movement,  and  that  of  the  little  finger  a  much  less  degree. 
The  distal  heads  of  the  four  inner  metacarpal  bones  are  bound 
together  by  the  transverse  metacarpal  ligament.     Flexion  of 
the  two  distal  phalanges,  without  flexing  the  first,  is  per- 
formed with  the  aid  of  the  extensor  tendon,  which  first  fixes 
the  proximal  phalanx.     In  extensor  paralysis,  therefore,  this 
movement   is   not   possible.     The   power   of   flexion   of   the 
distal  phalanx  alone  is  not  generally  possessed,   but  some- 
times   from   injury,    where    the   extensor   tendon   has    been 
ruptured  from  its  attachment  to  the  terminal  phalanx,  that 
phalanx  becomes  flexed  and  fixed,  the  condition  being  known 
as   mallet  finger.      The  middle   finger,   owing  to  its  greater 
length,  is  most  exposed  to  shocks  received  by  the  fingers,  and 
is  well  adapted  to  resist  these,  as  its  metacarpal  bone  rests 
on   the   cs   magnum,    which    again   communicates   with   the 
semilunar,  and  so  with  the  strongest  portion  of  the  radius. 
Fractures  of  the  metacarpal  bones  are  common,  the  first  being 
most  frequently  and  the  third  least  often  affected.     Fracture 
at  the  base  of  the  first  metacarpal  is  called  Bennett's  fracture 
('  stave  of  the  thumb  ').     Avulsion  of  one  or  more  fingers  may 
be  caused  by  machinery  tears  or  bites   of    certain  animals. 
In  such  cases  not  only  the  fingers,  but  also  the  tendons,  may 
be  dragged  out  from  the  forearm.     Where  only  a  single  tendon 
comes  away,  it  is  generally  that  of  the  flexor  profundus,  but 
all  the  tendons  may  be  so  torn.     As  the  palmar,  or  glenoid, 
ligaments  in  front  of  the  fingers  are  more  firmly  attached  to 
the  distal  than  the  proximal  bones,  they  are  carried  with  the 
distal  bones,  when  dislocated,  backwards,  and  cause  consider- 
able  difficulty  when  reduction  is   attempted.     The  palmar 


UPPER  EXTREMITY  437 

ligament  consists  of  a  plate  of  fibro-cartilage  firmly  attached 
to  the  base  of  the  phalanx  on  its  palmar  aspect,  and  but 
loosely  attached  to  the  proximal  bone.  The  two  sesamoid 
bones  of  the  thumb  are  developed  in  the  metacarpo-phalangeal 
plate,  and  a  single  sesamoid  bone  is  frequently  developed  in 
the  metacarpo-phalangeal  plate  of  the  index  finger  on  its 
radial  side.  In  the  case  of  the  thumb  the  outer  bone  gives 
attachment  to  the  abductor  and  outer  head  of  the  flexor 
brevis,  while  the  inner  gives  attachment  to  the  adductor  and 
inner  head  of  the  flexor  brevis. 

A   BACKWARD    DISLOCATION    OF   THE   THUMB    (Key's)    at   the 

metacarpo-phalangeal  joint  is  not  uncommon,  being  caused 
generally  by  .  forcible  hyperextension,  and  presents  con- 
siderable difficulty  in  reduction.  This  difficulty  has  been 
variously  attributed  to  the  backward  displacement  of  the 
plate  of  fibro-cartilage  forming  the  palmar  ligament,  which 
has  just  been  mentioned  as  causing  difficulty  in  the  fingers, 
and  which  carries  with  it  the  short  muscles  attached  to  the 
sesamoid  bones  ;  to  entanglement  of  the  long  flexor  tendon  ; 
locking  of  the  metacarpal  bone  between  the  lateral  ligaments, 
or  heads  of  the  flexor  brevis,  etc.  To  reduce  the  dislocation 
it  is  advised  to  extend  the  phalanx  till  at  right  angles  to  the 
metacarpal  bone,  and  while  in  this  position,  to  carry  the  base 
of  the  phalanx  over  the  metacarpal  head,  and  then  to  flex 
the  phalanx  suddenly.  Subcutaneous  section  of  the  palmar 
ligament  from  the  extensor  aspect  is  said  to  permit  of  easy 
reduction.  Amputation  of  the  thumb  with  its  metacarpal  bone 
is  best  done  through  a  vertical  incision  over  the  subcutaneous 
radial  border  of  the  metacarpal  bone.  The  metacarpal  bone 
is  excised  subperiosteally,  and  the  finger  removed  by  an 
elliptical  incision  at  the  lower  end  of  the  vertical  one. 
Amputation  of  the  fingers  is  frequently  performed  at  the  meta- 
carpo-phalangeal or  interphalangeal  joints.  In  the  former 
position  a  racket  incision  is  generally  best,  taking  care  to 
keep  the  racket  distal  to  the  web  of  the  finger,  while  the 
handle  of  the  racket  extends  upon  the  dorsal  surface  over 
the  joint.  In  the  case  of  the  index  and  little  fingers  the  handle 
of  the  racket  should  be  kept  toward  the  centre  of  the  hand, 
so  that  the  scar  will  not  present  on  the  pressure  surface. 
Further,  it  is  not  wise  to  remove  the  head  of  the  underlying 
metacarpal  bone,  as  it  weakens  the  hand  greatly.  At  the 


438  SURGICAL  ANATOMY 

interphalangeal  joints  the  knife  is  entered  dorsally  just  distal 
to  the  flexed  knuckle  ;  then,  having  opened  the  joint,  the 
edge  is  directed  distally,  and  a  long  palmar  flap  is  cut  from 
the  anterior  surface  of  the  phalanx.  The  bases  of  the  distal 
phalanges  should  be  saved  where  possible,  as  they  carry  the 
insertions  of  the  flexor  profundus  tendons.  If  the  lower 
half  of  the  middle  phalanx  can  be  preserved,  the  insertions 
of  the  flexor  sublimis  to  it  would  be  saved.  Where  tendons 
are  cut  within  their  sheaths,  as  at  the  first  interphalangeal 
joint,  they  generally  retract  markedly,  leaving  the  phalanx 
without  power,  and  the  gaping  sheath  also  makes  spread  of 
sepsis  probable  It  is  well,  therefore,  to  stitch  the  end  of 
the  divided  tendon  to  the  sheath,  and  close  the  mouths  of 
the  latter.  Removal  of  fingers  should  be  done  sparingly, 
particularly  in  the  case  of  the  thumb,  index,  and  little  fingers. 

The  Nerves  of  the  Upper  Extremity. 

The  SPINAL  ORIGINS  of  the  nerves  supplying  the  muscles 
of  the  upper  limb  are  :  adductors  and  abductors  of  shoulder 
(circumflex,  supra-  and  subscapulars) ,  fifth  and  sixth  cervical  ; 
flexors  of  elbow  (musculo-cutaneous),  fifth,  sixth,  and  seventh 
cervical  ;  extensors  of  elbow  (musculo-spiral) ,  sixth,  seventh, 
and  eighth  cervical  ;  flexors  of  wrist  and  hand  (median  group), 
sixth  and  seventh  cervical  ;  flexors  of  wrist  and  hand  (ulnar 
group),  seventh  and  eighth  cervical,  first  dorsal  ;  extensors 
of  wrist  and  hand,  and  supinators  (musculo  -  spiral  and 
posterior  interosseous) ,  sixth,  seventh,  and  eighth  cervical. 

The  median  nerve  supplies  the  flexor  sublimis  digitorum 
(and  part  of  the  flexor  profundus  by  the  anterior  interosseous), 
the  abductor,  opponens,  and  half  of  the  flexor  brevis  pollicis 
(superficial),  and  first  and  second  lumbricals. 

The  ulnar  nerve  supplies  part  of  the  flexor  profundus 
digitorum,  and  all  the  small  muscles  of  the  hand  not  supplied 
by  the  median. 

The  anterior  interosseous  of  the  median  supplies  the  flexor 
longus  pollicis,  pronator  quadratus,  and  part  of  the  flexor 
profundus. 

As  to  SENSATION  :  The  palmar  aspect  of  the  thumb  and 
two  and  a  half  outer  fingers  is  supplied  by  the  median,  the 
remaining  one^and  a  half  by  the  ulnar. 


UPPER  EXTREMITY  439 

Dorsally,  the  thumb  is  supplied  by  the  radial,  as  well  as 
the  first  phalanges  of  the  index,  middle,  and  radial  side  of 
the  ring  finger.  The  second  and  third  phalanges  of  the 
index,  middle,  and  half  of  the  ring  fingers  are  supplied  by  the 
median.  The  ulnar  side  of  the  ring  and  the  whole  of  the 
little  finger  are  supplied  by  the  ulnar. 

The  MUSCULO-SPIRAL  nerve  arises  from  the  fifth  to  the  eighth 
cervical  nerves.  It  gives  off  internal  and  upper  and  lower 
external  cutaneous  branches  in  the  upper  arm  ;  supplies  the 
triceps  and  anconeus  from  the  musculo-spiral  groove,  and  the 
brachialis  anticus,  supinator  longus,  and  extensor  carpi 
radialis  longior  after  piercing  the  external  intermuscular 
septum.  Its  posterior  interosseous  branch  in  the  forearm 
supplies  the  extensor  carpi  radialis  brevior,  supinator  brevis, 
extensors  of  the  fingers  and  thumb,  and  extensor  carpi 
ulnaris  muscle,  while  the  radial  branch  is  purely  sensory. 

The  nerve  is  frequently  injured  in  fractures  of  the  humerus, 
owing  to  its  close  relationship  to  the  bone,  and  by  undue 
pressure  on  the  arm  or  on  the  axilla  (as  in  crutch  paralysis). 
When  paralysis  of  the  nerve  occurs  the  extensors  of  the  limb 
are  affected,  causing  drop-wrist,  and  the  supinators  are  like- 
wise affected,  while  the  flexors  suffer  from  want  of  co-opera- 
tion. Where  the  lesion  occurs  below  the  middle  of  the 
forearm,  the  triceps  escapes.  Sensation  may  be  quite  un- 
affected. 

The  MEDIAN  NERVE  arises  from  the  sixth  to  the  eighth 
cervical  and  first  dorsal.  In  the  forearm  it  lies  between  the 
superficial  and  deep  muscles,  and  gives  off  muscular  branches 
to  the  pronator  radii  teres,  flexor  carpi  radialis,  flexor  sublimis 
digitorum,  and  palmaris  longus.  while  the  anterior  inter- 
osseous  branch  supplies  the  outer  half  of  the  flexor  profundus, 
flexor  longus  pollicis,  and  pronator  quadratus.  At  the  wrist  it 
lies  between  the  flexor  carpi  radialis  and  flexor  sublimis,  gives 
off  the  palmar  cutaneous  above  the  annular  ligament,  under 
which  it  passes  to  enter  the  palm,  where  it  divides  into  its 
terminal  branches,  after  supplying  the  abductor,  opponens, 
and  superficial  head  of  the  flexor  brevis  pollicis.  The  inner 
and  outer  terminal  branches  supply  the  two  first  lumbricals, 
and  sensation  to  the  palmar  aspect  of  the  thumb,  index, 
middle,  and  half  of  the  ring  finger,  and  to  the  dorsal  aspect 
of  the  terminal  phalanx  of  the  thumb,  and  of  the  two 


440 


SURGICAL  ANATOMY 


terminal  phalanges  of  the  index,  middle,  and  half  of  the  ring 
finger. 

In  the  palm  the  median  nerve  lies  under  the  superficial 
palmar  arch,  but  in  the  fingers  its  branches  are  superficial 
to  the  digital  arteries. 


FIG.  61. — CUTANEOUS  NERVES  OF  ARM. 


Front. 

Supra -acromial . 
Circumflex. 
Int.  cutan. 
Int.  cutan.  of  musculo-spiral  and 

intercosto-humeral. 
Ext.  cutan.  of  musculo-spiral. 
Musculo-cutan. 
Median. 
Ulnar. 


Back. 

1.  Supra-acromial. 

2.  Circumflex. 

3.  Int.  cutan.  of  musculo-spiral. 

4.  Intercosto-humeral. 

5.  Lesser  int.  cutaneous  (Wrisberg). 

6.  Ext.  cutan.  of  musculo-spiral. 

7.  Internal  cutan. 

8.  Musculo-cutan. 

9.  Ulnar. 
TO.   Radial. 

Parts  shaded  :  Median. 


Paralysis  of  the  nerve  is  most  often  produced  by  wounds 
of  the  forearm  or  wrist,  and  produces  inability  to  completely 
pronate  the  forearm,  and,  when  flexion  of  the  wrist  is 
attempted,  produces  ulnar  adduction.  The  thumb  is  extended 


UPPER  EXTREMITY  441 

and  adducted,  and  flexion  and  apposition  are  impossible, 
while  pasting  of  the  thenar  eminence  is  marked.  Flexion 
of  the  terminal  phalanges  of  the  index  and  middle  fingers 
(supplied  by  the  outer  portion  of  the  flexor  profundus)  is 
impossible,  as  is  likewise  flexion  of  all  the  second  phalanges 
(supplied  by  sublimis  and  profundus  together).  Flexion 
of  the  first  phalanges,  with,  at  the  same  time,  extension  of  the 
two  distal  phalanges,  is  possible,  from  the  action  of  the  inter- 
ossei  and  two  outer  lumbricales,  while  the  flexor  brevis 
minimi  digiti  will  also  act.  Sensation  may  be  completely 
lost  in  the  parts  supplied,  or  may  be  almost  unaffected. 

The  ULNAR  NERVE  arises  from  the  eighth  cervical  and  the 
first  dorsal.  It  gives  off  articular  filaments  to  the  elbow-joint, 
and  enters  the  forearm  between  the  heads  of  the  flexor  carpi 
ulnaris,  giving  off  thereafter  motor  branches  to  the  flexor 
carpi  ulnaris  and  inner  half  of  the  flexor  profundus  digitorum. 
Below  the  centre  of  the  forearm  it  gives  off  a  palmar  cutaneous 
branch,  which  supplies  the  hypothenar  eminence  and  central 
area  of  the  palm,  and  a  dorsal  cutaneous  branch,  which 
communicates  with  the  radial,  and  supplies  the  dorsum  of 
the  hand  on  its  ulnar  side,  and  also  the  dorsum  of  the  little 
finger,  and  of  the  ulnar  border  of  the  ring  finger.  The  trunk 
enters  the  palm  by  crossing  the  annular  ligament  superficially, 
and  divides  into  superficial  and  deep  branches,  the  former 
supplying  the  palmaris  brevis,  and  the  hypothenar  skin  and 
skin  of  the  little  finger,  and  ulnar  border  of  the  ring  finger  on 
both  palmar  and  dorsal  aspects.  The  deep  branch  supplies 
all  the  interossei,  two  inner  lumbricales,  and  all  the  outer- 
short  muscles  of  the  hand,  except  the  abductor,  opponens, 
and  half  of  the  flexor  brevis  of  the  thumb. 

The  ulnar  nerve  is  most  often  damaged  about  the  elbow, 
but  may  also  be  wounded  about  the  wrist.  In  paralysis  of 
the  nerve,  flexion  of  the  wrist  is  accompanied  by  radial  devia- 
tion. The  thumb  cannot  be  adducted,  and  the  little  finger 
is  almost  completely  paralyzed,  the  hypothenar  eminence 
atrophying.  The  ring  finger  cannot  be  flexed  at  the  meta- 
carpo-phalangeal  joint,  nor  extended  at  the  interphalangeal 
joints,  owing  to  paralysis  of  the  interossei  and  inner  lum- 
bricales, while  the  index  and  ring  fingers,  partly  supplied  by 
the  two  outer  lumbricales,  are  less  markedly  affected. 

In  the  later  stages  a  claw-hand  is  developed  from  the  un- 


442  SURGICAL  ANATOMY 

restrained  action  of  the  flexors  and  extensors,  producing 
overextension  of  the  first  and  flexion  of  the  second  and  third 
phalanges. 

As  in  the  other  nerves  described,  loss  of  sensation  is  often 
partial,  owing  probably  to  the  overlapping  of  the  sensory 
areas  supplied  by  the  various  nerves. 

ERB'S  BRACHIAL  PARALYSIS  is  one  which  affects  the  deltoid, 
biceps,  brachialis  anticus,  supinator  longus,  and  sometimes 
the  supra-  and  infraspinati  and  supinator  brevis.  It  is  due 
to  injury  to,  pressure  upon,  or  disease  of  either  (a)  the  motor 
columns  of  the  cord  supplying  particularly  the  fifth  and  sixth 
cervical  roots,  or  (b)  that  part  of  the  brachial  plexus  where 
the  motor  tracts  for  the  involved  muscles  have  not  yet  divided 
into  the  different  nerve  trunks. 

Erb's  point,  which  lies  fully  J  inch  anterior  to  the  border  of 
the  trapezius  on  a  line  from  the  sterno-clavicular  articulation 
to  the  seventh  cervical  spine,  is  that  selected  for  stimulation 
of  the  affected  muscles. 

A  somewhat  similar  condition  is  met  with  in  infancy,  due 
probably  to  traction  on  the  cords  of  the  brachial  plexus,  from 
pulling  on  the  head  of  the  child  during  delivery  and  exerting 
great  pressure  on  the  supraclavicular  fossa.  The  arm  is 
rotated  markedly  inwards,  the  ulnar  border  of  the  hand 
presenting  anteriorly,  the  position  resembling  that  found  in 
subspinous  dislocation  of  the  shoulder.  This  condition  may 
persist  to  adult  life  and  cause  much  limitation  of  movement 
of  the  affected  limb. 


INDEX 


The  number  given  first  indicates  the  principal  reference. 


ABDOMEN,  177 

boundaries  of,  177 
fasciae  of,  239 
inframesocolic    compartment 

of,  202 

integuments  of,  177 
muscles  of,  179 
nerves  of,  183 
palpation  of,  183 
parietes  of,  177 
superficial  divisions  of,  177 
supramesocolic  compartment 

Of,   202,   205 

surface  anatomy  of,  177 
transverse  furrows  of,  1 78 
vessels  of,  248 
Abdominal  :  aneurism,  248 
aorta,  248 
ascites,  177,  231 
incisions,  178,  179 
rings,  189,  191 
viscera,  203-247 
wall,  abscess  of,  182,  200 

anastomosis  in,  179,  185 
blows  on,  183 
extravasation    of     urine 

into,  178 

lymphatics  of,  179 
nerves  of,  183. 
reflex    nervous    mechan- 
ism of,  183 
vessels  of,  178,  185 
Aberrant  obturator  artery,  193 
Abnormalities  of  brachial  artery, 

398 

Abscess,  abdominal,  182,  200 
acetabular,  242,  321 
alveolar,  95 
appendicular,  221 
axillary,  394 
cerebral,  20,  34 
cerebellar,  5 1 
extradural,  17,  50 
extraperitoneal,  241 


Abscess,  gluteal,  301 
hepatic,  223 
Hilton's  mode  of  evacuating, 

iliac,  241 

intracerebral,  5 1 

ischio-rectal,  297 

mammary,  160 

mastoid,  49 

mediastinal,  161 

orbital,  61 

palmar,  5 

parotid,  91 

perineal,  286 

perinephric,  245 

periurethral,  286 

popliteal,  331 

post-pharyngeal,  90 

prevertebral,  117 

prostatic,  268 

psoas,  241,  141 

renal,  245 

retropharyngeal,  141,  207 

retroperitoneal,  241 

subphrenic,  213,  221 

temporal,  9 

temporo-sphenoidal,  21,  51 

thecal,  428 

tropical,  233 

zygomatic,  97 

|    Accessory  sinuses  of  nose,  80 
anterior  group,  82 
posterior  group,  81 

thyroids,  131 
Accommodation,  66,  72 
Acetabulum,  312 

abscess  arising  from,  242 

fractures  of,  312 
Achillis,  tendo,  349 
Acne  of  face,  85 
rosacea,  74 
Acromion  process,  381 

fracture  of,  381 
angle  of,  376 

443 


444 


SURGICAL  ANATOMY 


Acromio  -  clavicular    articulation, 

379 

dislocation  of,  380 
Addison's  disease,  246 
Adductor  region,  312 

tubercle,  329 
Adenoids,  1 10 
Aditus  ad  antrum,  48 
Adrenals,  246 
Agger  nasi,  76 
Ague  cake,  238 
Air  in  veins,  135 

embolism,  135 
Alae  nasi,  74 
Alcock's  canal,  290 
Alexander's  operation,  283 
Allantois,  186 
Amazia,  160 
Amnion,  186,  187 
Ampulla  of  milk  ducts,  156 
of  Vater,  235 

gall-stones  in,  235 
rectal,  290 

Amputation  (see  under  Arm,  Leg, 
etc.,  and  name  of  inventor) 
neuroma,  328 
'    Amygdaloid  nuclei,  23 
Anaesthesia,  pupil  in,  73 

tongue  in,  105 
Anal  canal,  292 

congenital     defects      of, 

296 

development  of,  295 
digital    examination    of, 

291 

lymphatics  of,  294 
mucous     membrane     of, 

293 

nerves  of,  294 

relations  of,  291 

triangle,  289 

valves,  293 

vessels,  293 

white  line,  293 
Anastomosis  (see  under  Ligature 

of  Arteries) 

artificial  portal  systemic,  231 
crucial,  302 

parietal  and  visceral,  248 
patellar,  332 
Aneurism,  aortic,  167 

arterio-venous,  54,  407 
axillary,  392 
carotid,  133 
cerebral,  29 
cirsoid,  7 
femoral,  309 
gluteal,  302 


Aneurism,  innominate,  138 

popliteal,  332 

posterior  tibial,  350 

subclavian,  139 

treatment  of,  167 
Angina,  Ludwig's,  102,  122 
Angular  curvature  of  spine,  141 
Angulus  sternalis,  151 
Ankle,  353 

fasciae  of,  358 

joint,  361 

amputation  at,  370 
dislocation  of,  363 
effusion  into,  361 
fractures  about,  363 
ligaments  of,  361 
nerves  of,  362 
sprain,  358,  362 
sprain  fractures  at,  362 
synovial    membrane    of, 
362 

surface  anatomy  of  the,  353 

tendons  of,  358 
Ankyloblepharon,  57 
Annular  ligaments  of  ankle,  358 

of  wrist,  423,  427,  431 
Ano-coccygeal  body,  293 
Annulus  urethralis,  260 
Antecubital  fossa,  407 
Anterior  chamber  of  eyeball,  69 

fontanelle,  1 1 

fossa  of  skull,  12 

palatine  canal,  106 

synechiae,  65 
Antrum,  duodenal,  211 

mastoid,  48 

of  Highmore,  83 

pylori,  205 
Anus,  293 

artificial,  226 

development  of,  295 

distension  of,  293 

epithelioma  of,  296 

fissure  of,  297 

fistula  of,  297 

imperforate,  296 
Aorta,  abdominal,  248 

compression  of,  322 

aneurism  of,  167,  248 

arch  of,  166 

ascending,  166 

descending,  166 

isthmus  of,  166 

sinuses  of,  166 

spindle  of,  166 

thoracic,  166 
Aortic  valve  of  heart,  164 
Apex  of  lung  in  neck,  113 


INDEX 


445 


Aponeuroses.     See  Fasciae 
Apoplexy,  cerebral,  29 

pulmonary,  173 
Appendices  epiploicae,  226 
Appendicitis,  220 

abscess  following,  221 

operative  treatment  for,  221 

peritonitis  following,  220 
Appendix  vermiformis,  218 
Aqueduct  of  Fallopius,  5  3 

of  Sylvius,  24 
Aqueous  humour,  69 
Arachnoid,  cerebral,  17 

spinal,  144 
Arches  of  foot,  354 

of  palate,  107 

of  palm  (arterial),  423 
Arcus  senilis,  65 
Area,  motor,  20 

Rolandic,  20 

Argyll -Robertson  pupil,  72 
Arm,  394 

amputation  of,  403 

fascia  of,  395 

integuments  of,  395 

lymphatics  of,  396 

nerves  of,  398 

surface  anatomy  of,  394 

vessels  of,  395 

Arterio-venous  aneurism,  309 
Artery,  aberrant  obturator,  193 

acromio-thoracic,  376,  391 

anastomotica  magiia,  397 

anterior  tibial,  347 

aorta,  164,  248 

axillary,  390,  376 

brachial,  396,  395 

bronchial,  173 

carotid,  132,  377 

central,  of  retina,  68,  71 

cerebral,  29 

ciliary,  71 

circumflex,  arm,  391,  399 
iliac,  185 

cceliac  axis,  205 

coronary,  205 

cremasteric,  271 

cystic,  232 

dental,  inferior,  94 

dorsalis  pedis,  359,  355 

epigastric,  deep,  185 
superficial,  306 

external  carotid,  134 

external  iliac,  256 

external  mammary,  391 

facial,  5,  85,  122 

femoral,  309 

gluteal,  302 


Artery,  haemorrhoidal,  293 
hepatic,  231 
hyaloid,  71 
iliac,  256 

inferior  dental,  94 
innominate,  138,  377 
intercostal,  154 
internal  carotid,  134 

iliac,  256 

mammary,  155 
iiiterosseous,  416 
lingual,  103,  121,  122 
lenticulo-striate,  29 
mammary,  internal,  139 
mesenteric,  inferior,  226 

superior,  216 
middle  cerebral,  29 

colic,  226 

meningeal,  26,  4,  13 
obliterated  hypogastric,    186, 

257 

obturator,  193 
occipital,  6 
ophthalmic,  71 
ovarian,  277 
peroneal,  350 
plantar,  360,  355 
popliteal,  332 
posterior  interosseous,  417 

tibial,  349 
profunda  brachialis,  397 

femoris,  309 
pulmonary,  164 
radial,  416,  413,  430 
ranine,  103 
renal,  244 
sciatic,  302 
spermatic,  272 
splenic,  236,  237 
subclavian,  136,  377 
subscapular,  391 
superior  intercostal,  139 

thoracic,  390 
temporal,  superficial,  6 
thoracic  aorta,  166 

arteries,  391,  376 
thyroid,  inferior  and  superior, 
129,  130 

axis,  139 
tibial,  anterior,  347,  359 

posterior,  349,  360 
ulnar,  414-416,  430 
umbilical,  186 
uterine,  277 
vas  deferens,  273 
vertebral,  139 
Willis,  circle  of,  28 
Aryteno-epiglottic  folds,  124 


446 


SURGICAL  ANATOMY 


Ascites,  177,  231 
Asterion,  3 
Astigmatism,  64 
Astragalus,  366 

dislocations  of,  363,  366 

fractures  of,  367 

in  congenital  talipes,  367 
Asymmetry  of  head,  i 
Atheromatous  cyst,  5 
Atrium  of  nose,  76 
Attic  of  tympanum,  45 
Auditory  meatus,  external,  43 
Auerbach's  plexus,  217 
Auricle,  supernumerary,  42 
Auricular  point,  3 
Avulsion  of  scalp,  6 

of  upper  limb,  377 
Axes  of  rotation  of  eyeball,  60 
Axilla,  388 

boundaries  of,  388 

contents  of,  390 

folds  of,  376,  388,  390 

surface  anatomy  of,   388 

suspensory  ligament  of,  389 

tumours  of,  393 

wounds  of,  393 
Axillary  abscess,  394 

aneurism,  392 

fascia,  389 

lymphatic  glands,  393 
affections  of,  393 

nerves,  393 

vein,  392 

Band,  ilio-tibial,  301,  307 
Bartholin's  duct,  102 

glands,  284 
Basal  ganglia,  23 
Base  of  skull,  12 

fossae  of,  12 

fracture  of,  14 
Bell's  paralysis,  39 
Bennett's  fracture,  436 
Bezold's  aperture,  53 
Biceps  muscle,  rupture  of,  383 
Bicipital  fascia,  407 

sulci,  394 
Bile-duct,  233 

common,  234,  233 

obstruction  of,  234,  235 
operations  on,  235 
Biliary  colic,  235 

Black  eye,  distinction  from  frac- 
ture of  orbital  plate,  55 
Bladder,  257 

coats  of,  259 

development  of,  186 

distension  of,  259 


Bladder,  extroversion  of,  261,  267 
fasciculated,  259 
female;  261 
fistulas  of,  261 
hernia  of,  261 


hypertrophy  of,  259 
inflammation  of,  26 


61 

ligaments  of,  257 

lymphatics  of,  260 

nerves  of,  260 

of  child,  257 

orifice  of,  257 

prolapse  of,  261 

prostatic  pouch  of.  260 

puncture  of,  259 

relations  of,  259 

rupture  of,  261 

sacculation  of,  259 

stone  in,  261 

trig  ones  of,  259 

tumours  of,  261 

ulcers  of,  261 

vessels  of,  260 

wounds  of,  261 
Blepharitis,  55 
Blepharo-chalasis,  56 

spasm,  56,  65 
Blind  spot,  68 
Bones,  blood-supply  of,  342 

epipteric,  1 1 

interparietal,  34 

of  cranial  vault,  9 

of  forearm,  416 

of  leg,  351 

surgical    affections    of,     341, 
326 

turbinal,  77 

Wormian,  1 1 
Bougie,  O3sophageal,  176 
Bowman's  glands,  76 
Brachial  artery,  abnormalities  of, 
398 

plexus,  392,  377 
Brachycephalic  skulls,  i 
Brain,  19 

abscess  of,  20,  34 

basal  ganglia,  23 

centres  of,  20 

concussion,  33 

convolutions,  20 

fissures,  20 

membranes,  16 

motor  centres,  20 

pulsation  of,  25 

relations  to  surface,  19 

tumours  of,  25,  34 

vessels  of,  29 
Branchial  arches,  137 


INDEX 


447 


Branchial  clefts,  137 

cysts,  137 

fistulas,  137 

recesses,  137 

Breast,  156.     See  Mamma 
Bregma,  2 
Broad  ligaments,  280 

contents  of,  280 
relations  of,  280 
Broca's  lobe,  20 
Bronchi,  168 

foreign  bodies  in,  168 
Bronchocele.     See  Goitre 
Bruch,  membrane  of,  67 
Brunner's  glands  in  burns,  21 1 
Bryant's  mode  of  dividing  palate 
muscles,  108 

triangle,  300 
Bubo,  305 
Bubonocele,  191 
Buccal  cavity,  101 

pad  of  Bichat,  85 

portion  of  pharynx,  no 
Bulb  of  corpus  spongiosum,  265 
Bulbar  paralysis,  41 
Bulla  ethmoidalis,  78,  82 

frontalis,  82 
Bunion,  365 

Burdach,  columns  of,  32 
Burn,  ulcer  after,  211 
Bursa,  elbow,  408 

great  palmar,  428 
trochariter,  301 

intertubercular,  385 

ischial  tuberosity,  302 

knee,  330 

ovary,  280 

patellar,  330 

popliteal,  334 

subacromial,  383 

subscapular,  384 

thyro-hyoid,  123 
Buttock.     See  Gluteal  region 

Caecal  folds  and  fossae,  219 

hernia,  218 
Caecum,  217 

abnormal  positions  of,  218 

adult  type  of,  218 

development  of,  218 

foreign  bodies  in,  218 

hernia  of,  218 

infantile  type  of,  218 

inflammation  of,  220 

in  intestinal  obstruction,  218 

nerves  of,  220 

peritoneum  of,  218 

sacculation  of,  218 


Caecum,  ulceration  of,  218 

vessels  of,  219 

volvulus  of,  218 
Calcaneo-astragaloid- joint,  364 

cuboid  joint,  364 
Calcaneum,  366 
Calcar  femorale,  317 
Canal,  Alcock's,  290 

crural,  193 

facial,  46 

Hunter's,  324 

hyaloid,  71 

inferior  dental,  92 

inguinal,  188 

lachrymal,  59 

of  Nuck,  282,  198 

of  Petit,  71 

of  Schlemm.  64,  72 

of  Stilling,  7 1 

of  Wirsung,  236 

palatine,  106 

semicircular,  54 
Canaliculi,  lachrymal,  59 
Cancer  en  cuirasse,  159 
Cancrum  oris,  85 
Canine  fossa,  85,  92 
Canthi,  56 
Capitellum,  409 
Capsule,  external,  of  brain,  22 

internal,  of  brain,  22 

of  Glisson,  228 

of  hip-joint,  315 

of  kidney,  243 

of  knee-joint,  335,  338 

of  lens,  70 

of  parotid  gland,  116 

of  prostate,  268 

of  shoulder- joint,  384 

of  submaxillary  gland,  116 

of  Tenon,  62 
Caput  Medusae,  179 
Garden's  amputation,  344 
Cardiac  area,  superficial,  163 

orifice  of  stomach,  203 
Cario-necrosis,  366 
Carnochan's  operation,  88 
Carotid  aneurism,  133 

artery,  132 

anastomoses  of,  133,  134 
ligature  of,  133,  134 

lymphatics,  132 

region  of  neck,  132 

sheath,  132 

tubercle,  133 
Carpal  arches,  430,  431 

bursa,  great,  428 
Carpus,  articulation  of,  433 

disease  of,  434 


443 


SURGICAL  ANATOMY 


Cartilages,  lateral,  of  nose,  74 

septal,  of  nose,  75 

tarsal,  54 

Y-shaped,  of  acetabulum,  312 
Caruncle,  lachrymal,  56,  57 

urethral,  262 
Castration,  274 
Cataract,  congenital,  70 

senile,  70 

traumatic,  70 
Catheter,  coude,  269 

Eustachian,  78 

male,  264 

prostatic,  269 
Cauda  equina,  143 
Caudate  lobe  of  liver,  229 

nucleus,  23 

Cavernous  sinus,  27,  61 
Cavum  Meckelii,  36 
Centres,  defaecation,  295 

micturition,  260 

of  brain,  19 

of  cord,  146 

of  medulla,  32 
Cephalhaematoma,  8 
Cerebellar  abscess,  22 

localization,  22 

tracts,  31,  33 

tumour,  22 
Cerebellum,  30,  4,  22 

peduncles  of,  30 
Cerebral  abscess,  25,  20,  34 

aneurism,  29 

circulation,  26,  28 

convolutions,  20 

crura,  30 

embolism,  29 

haemorrhage,  29 

localization,  4,  19 

membranes,  16 

sinuses,  26 

tumour,  25,  34 

vessels,  29 

Ceruminous  glands,  43 
Cervical  abscess,  116 

cord,  32 

enlargement,  143 

fascia,  114 

fistulas,  137 

glands,  122,  132,  137 

nerves,  1 17 

ribs,  137 

sympathetic,  133 

tumours,  130,  137 
Cervico-pericardiac  fascia,  161 
Cervix  uteri,  275 
Chalazion,  57 
Chambers  of  eyeball,  69 


Charcot,  aneurism  of,  29 

Chassaignac's  tubercle,  133 

Check  ligaments,  62 

Cheek,  85 

Chemosis,  57 

Chest,  deformities  of,  150 

female,  150 

surface  anatomy  of,  1 50 

variations  in  shape  of,  1 50 

want  of  symmetry  of,  150 

wounds  of,  165 
Chimney-sweep's  cancer,  274 
Choanae,  75 
Cholecystectomy,  235 
Cholecystenterostomy,  235 
Cholecystostomy,  234 
Cholecystotomy,  234 
Choledochotomy,  235 
Cholesteatoma,  54 
Chopart's  amputation,  370 
Chordee,  267 
Chorio-capillaris,  67 
Chorpid  plexuses,  18 
Chorioid,  67 

rupture  of,  67 

tumour  of,  67 
Chorioidal  fissure,  66 
Chyle  cysts,  217 
Ciliary  arteries,  71 

body,  6  6 

muscle,  66 

nerves,  72 

processes,  66 
Circle  of  Willis,  28 
Circular  sinus,  27 
Circulus  iridis,  71 
Circumcision,  266 
Circumvallate  papillae  of  tongue, 

103 

Cirsoid  aneurism,  7 
Cisterna  magna,  18 

pontis,  1 8 
Clarke's  column,  33 
Claustrum,  22,  23 
Clavicle,  380 

articulations  of,  378,  379 

dislocations  of,  378,  380 

fractures  of,  380 

movements  of,  379 

ossification  of,  381 

periosteum  of,  381 
Clavi-pectoral  region,  377,  375 
Claw-hand,  441 
Cleft,  median,  of  lower  lip,  101 

of  upper  lip,  101 

palate,  107 

recesses  (branchial),  137 
Clergyman's  sore-throat,  124 


INDEX 


449 


Clitoris,  284 

Cloaca,  295 

Clubbing  of  finger-tips,  425 

Club-foot.     See  Talipes 

Coccygodynia,  251 

Coccyx,  251 

Cochlea,  54 

Cock's  operation,  288 

Coeliac  axis,  248 

Colitis,  220 

Colles's  fascia,  285,  178,  265 

fracture,  420 
Coloboma  facialis,  88,  101 

of  iris,  66 

of  lower  eyelid,  88,  57 

of  upper  eyelid,  57 
Colon,  ascending,  222 

descending,  224 

hepatic  flexure  of,  223 

hernia  of,  223 

iliac,  224 

lymphatics,  226 

nerve-supply,  226 

operations  on,  225 

pelvic,  224 

peritoneum  of,  224 

position  of,  222 

ptosis  of,  223 

splenic  flexure  of,  223 

transverse,  223 

volvulus  of,  225 
Colotomy,  inguinal,  225 

lumbar,  225 
Column  of  Clarke,  33 

of  Goll  and  Burdach,  32 

vertebral,  139 
Columns  of  Morgagni,  293 
Compression  of  brain,  34 

of  cord,  146 
Concussion  of  brain,  33 

of  cord,  145 
Conditions      resembling      femoral 

hernia,  305 
inguinal   hernia,    197,    272, 

273 

Condyles  of  femur,  340 
Congenital  dislocation  of  hip,  319 
exomphalos,  187 
fistula,  137 
hernia,  197. 
hydrocele,  197 
malformations    of    anus    and 

rectum,  295 
of  bladder,  261 
of  penis,  266 
of  pinna,  42 
talipes,  367 
tumour  of  sterno-mastoid,  1 19 


Conjoined  tendon,  180,  188 
Conjunctiva,  57 
fornices  of,  57 
nerves  of,  58 
vessels  of,  58 
Conjunctivitis,  58 
Conus  medullaris,  143 
Constipation,  224 
Contre-coup,  fracture  by,  1 1 
Convolutions  of  brain,  20 
Cooper's  amputation,  370 
Coraco-acromial  arch,  383 

-clavicular  attachment,  379 
Coracoid  process,  383,  375 

fracture  of,  382 
Cord,  spermatic,  271 

hydrocele  of,  197 
spinal,  I43-32 

injuries  of,  145-146 
umbilical,  185 
vocal,  125 
Corectopia,  66 
Cornea,  64 

herpes  of,  65 

inflammation  of  (keratitis),  65 
lymphatic  canals  of,  64 
nerves  of,  65 
ulceration  of,  65 
wounds  of,  65 
Coronal  suture,  2 
Cor  on  oid  fossa,  408 
process,  409 

fracture  of,  412 
Corpora  cavernosa,  265 
geniculata,  23 
quadrigemina,  23 
striata,  23 

Corpus  callosum,  24 
Highmori,  272 
spongiosum,  26 
striatum,  23 
Costal  cartilages,  153 

fracture  of,  153 

Costo-coracoid  membrane,  389 
Cotyloid  notch,  313 
Course  of  tracts  in  cord,  33 
Cowper's  glands,  263 
Cranial  bones,  9 
fossae,  12 
meningocele,  3 
necrosis,  9 
nerves,  35 
points,  2 
sutures,  1 1 
vault,  9 
Craniotabes,  9 
Cranium,  5 

Cribriform  fascia,  193,  308 
29 


450 


SURGICAL  ANATOMY 


Cricoid  cartilage,  1 1 2 
Crico- thyroid  membrane,  126 
Crista  urethralis,  263 
Crucial  anastomosis,  302 

ligaments  of  knee,  339 
Crural  canal,  193,  309 

nerve,  311,  372 

septum,  193 
Crus  cerebri,  30 
Crusta,  30 

Crutch  paralysis,  397,  439 
Cryptorchismus,  273 
Cuboid  bone,  367 
Cuneiform  bones,  dislocation,  367 
Curves  of  spines,  140 
Cut  throat,  123 
Cyclitis,  67 

Cynanche  tonsillaris,  109 
Cyst,  atheromatous,  5 

chyle,  217 

dermoid,  73,  102 

hydatid,  174 

mesenteric,  217 

of  breast,  160 

of  neck,  137 

of  urachus,  186 

ovarian,  282 

pancreatic,  236 

tarsal,  55 
Cystic  duct,  calculus  impacted  in, 

234 
mucous     membrane     of, 

234 

hygroma  of  neck,  137 
Cystitis,  261 
Cystocele,  261 
Cystotomy,  262 

Dacryocystitis,  59 
Dartos,  274 
Darwin's  tubercle,  42 
Dangerous  area  of  eye,  67 

of  scalp,  5 

Defaecation  centre,  295 
Deltoid,  bursae,  383 

insertion,  394 

muscle,  382 

paralysis  of,  383 

region,  382,  376 

tubercle,  375,  399 
Dental   caries,    reflex    effects    of, 

94 

Dentition,  94 
Dermoids,  cervical,  102 

ovarian,  282 

sacral,  250 

thyro-glossal,"  102 
Dextro-cardia,  165 


Diagnosis,    anatomical    causes   of 

mistakes  in,  194,  202,  214,  273 
Digastric  triangle,  121 
Diploe,  10 

veins  of,  10 
Diplopia,  89 

Direct  inguinal  hernia,  190 
Dislocation.     See  Joints  involved 
Dolichocephalic  skulls,  i 
Dorsal  enlargement  of  cord,  143 
Dorsum  ilii,  dislocation  of  head  of 

femur  on  to,  318 
Double  chin,  1 14 

pulse,  421 
Douglas,  pouch  of,  275,  291 

semilunar  fold  of,  180 
Drop-wrist,  439 
Duchenne's  paralysis,  41 
Duct,  Bartholin's,  102 

bile,  233 

cystic,  234 

ejaculatory,  263 

hepatic,  233 

lactiferous,  156 

Miillerian,  279,  266 

nasal,  59,  78 

naso-frontal,  78 

of  Gaertner,  282 

of  Rivini,  102 

of  Santorini,  236 

pancreatic,  236 

parotid,  91 

Stenson's,  91 

thoracic,  249 

thyro-glossal,  102 

vitello-intestinal,  186 

Wharton's,  102 

Wirsung's,  236 

Wolffian,  266 
Ductus  venosus,  230 
Duodeno-jejunal  flexure,  211 

junction,  21 1 
Duodenum,  210 

antrum  of,  211 

flexures  of,  211 

fossa  of,  213 

haemorrhage  from,  213 

papilla  of,  211,  234 

peritoneum  of,  211 

pouch  of,  213 

relations  of,  211 

rupture  of,  213 

strictures  of,  213 

suspensory  muscle  of,  211 
ulcer  of,  211 

vessels  of,  213 
Dupuytren's  contraction,  427 

fracture,  363 


INDEX 


Dura  mater,  16 

inflammation       of        (pachy- 
ftieningitis),  19 

of  brain,  16 

of  cord,  144 

vessels  of,  26 
Dysphagia,  175 

Ear,  42 

bleeding  from,  15 

cough,  40,  43 

frost-bite  of,  42 

haematoma  of,  42 

internal,  54 

middle,  45 

nerves  of,  43,  44,  53 

pinna,  42 

polypi  of,  43 

serous  discharge  from,  16 

sneezing,  43 

tophi  in,  42 

tumours,  44 

vomiting,  43 

yawning,  43 
Ectopia,  caecal,  218 

cordis,  152,  165 

intestinal,  187 

testis,  273 

vesicae,  261 
Ectropion,  55 

Ejaculatory  ducts,  263,  267,  270 
Elbow,  bursac,  408 

dislocations  of,  412 

excision  of,  411 

fractures  of,  412 

gland  of,  407 

integuments  of,  405,  408 

joint,  408 

disease  of,  410 

ligaments  of,  409 

region  of,  404 

sprains  of,  413 

surface  anatomy  of r  404 

synovial  membrane  of,  410 

veins  of,  405 
Elephantiasis,  274 
Embolism,  air,  135 

cerebral,  29 

of  central  artery  of  retina,  68 
Eminence,  parietal,  4 
Emissary  veins  of  skull,  10 
Emmetropia,  64 
Emphysema,  171 
Empyema,  171 
Encephalocele,  19 
Encysted  hernia,  197 

hydrocele  of  cord,  197 
Endognathion,  107 


Endothoracic  fascia,  154 
Enterectomy,  216 
Enter orrhaphy,  216 
Enterotomy,  216 
Enter optosis,  214 
Entropion,  55 
Epicanthus,  57 
Epicondyle,  fractures  of,  402 
Epididymis,  271 

globus  major  of,  271 

globus  minor  of,  271 
Epididymitis,  273 
Epigastrium,  177 
Epiglottis,  103,  124 
Epilepsy,  34 
Epiphora,  56 
Epiphyseal  plates  of  long   bones, 

341 

Epiphysis,  acromial,  381 
coracoid,  382 
femoral,  340 
humeral,  400,  402 
olecranal,  412 
rule  regarding  union  to  shaft, 

402 

tibial,  341 
Epiplocele,  202 
Epipteric  bone,  1 1 
Epispadias,  267 
Epis taxis,  77 
Epitympanic  recess,  45 
Erb's  brachial  paralysis,  442 
Erb's  point,  442 
Erectile  body,  76 
Eruption  of  teeth,  94 
Estlander's  operation,  172 
Ethmoidal  bulla,  82 
cells,  8 1 

anterior  group,  82 
posterior  group,  81 
Eustachian  catheter,  78 
tube,  47,  109 

isthmus  of,  47 
mouth  of,  48 

Excision.     See  Particular  joint 
Exognathion,  107 
Exomphalos,  187 
Exophthalmic  goitre,  130 
Extensor  paralysis  of  hand,  436 
External  abdominal  ring,  191,  189 
auditory  meatus,  43 
abscess  of,  43 
bony  segment  of,  43 
cartilaginous  segment  of, 

43 

exostosis  of,  44 
in  infant,  43 
nerves  of,  43 

29 — 2 


452 


SURGICAL  ANATOMY 


External  auditory  meatus,  polypi 
of,  mistakes  regarding, 

43 

skin  of,  43 

semicircular  canal,  48 
trigone  of  bladder,  259 
Extracapsular  fracture  of  femur, 

317 
Extradural  abscess,  17 

haemorrhage,  17 
Extraperitoneal  abscess,  241 

tissue,  182,  421 

Extravasation  of  urine,  264,  287 
between    layers    of    tri- 
angular ligament,  264 
into  perineum,  265 
Extroversion  of  bladder,  267 
Eyeball,  62 

anterior  chamber  of,  69 

coats  of,  64 

dangerous  area  of,  67 

excision  of,  67 

lens,  69 

movements  of,  60 

muscles  of,  60 

nerves  of,  72,  60 

posterior  chamber  of,  69 

rupture  of,  64 

vessels  of,  71 

vitreous,  70 
Eyebrows,  54 
Eyelashes,  55 
Eyelids,  54 

canthi  of,  56 

cartilages  of,  54 

coloboma  of,  57,  88 

cysts  of,  55 

lymphatics  of,  56 

muscles  of,  55 

nerves  of,  55 

oedema  of,  5  5 

septum  orbitale  of,  57 

vessels  of,  56 

Face,  85 

development  of,  88 

lymphatics  of,  86 

nerves  of,  86 

skin  of,  85 

surgical  affections  of,  86 

vessels  of,  85 
Facial  canal,  46,  53 

neuralgia,  37,  87 

paralysis,  38,  86,  101 
Faecal  fistula,  186 
Fainting,  161,  206 
Fallopian  tube,  280 

ampulla  of,  280 


Fallopian  tube,  fimbriae  of,  280 
inflammation  of,  281 
infundibulum  of,  280 
isthmus  of,  280 
mesosalpinx  of,  280 
ostia,  280 
pregnancy  in,  281 
rupture  of,  281 
Fallopius,  aqueduct  of,  53 
False  cords,  125 

passages,  264 
Falx  cerebri,  17 
Farabceufs  amputation,  353 
Fascia,  abdominal,  240 

axillary,  389,  390 

bicipital,  407 

bucco-pharyngeal,  no 

cervical,  114 

cervico-pericardiac,  161 

cremasteric,  182 

cribriform,  194,  308 

endothoracic,  154,  168 

iliac,  240,  191 

infundibuliform,  189 

intercolumnar,  191 

lata,  193,  308 

lumbar,  239 

obturator,  251 

of  Abernethy,  256 

of  arm,  395 

of  Colles,  285,  178,  265 

of  Scarpa,  285 

of  thigh,  307 

palmar,  426 

parotid,  89 

pectoral,  156 

pelvic,  251 

perineal,  285 

plantar,  357 

popliteal,  331 

pretracheal,  116,  135 

prevertebral,  116 

psoas,  239 

rectal,  291 

recto-vesical,  25 1 

renal,  243 

temporal,  9 

transversalis,  182,  189,  191 

triangular,  191 

vertebral,  239 
Fauces,  isthmus  of,  io(> 

pillars  of,  106 

Female  generative  organs,  275 
Femoral  artery,  309 

aneurism  of,  308 
ligature  of,  309 

canal,  193,  308 

hernia,  191 


INDEX 


453 


Femoral  hernia,  bladder  in,  194 

,  conditions       resembling, 

305,  308,  311 
contrasted  with  inguinal, 

191,  194 
course  of,  193 
radical  cure  of,  199 
strangulation  of,  198 
taxis  in,  194 
lymphatic  glands,  306 
phlebitis,  310 
ring,  305 
sheath,  309,  191 
trigone,  255 
vessels,  309 
Femur,  325,  314 

adductor  tubercle  of,  329 
condyles  of,  340 
dislocations  of,  317 
fractures  of,  315,  325,  341 
great  trochanter  of,  313 
head  of,  314 
lower  extremity  of,  340 
neck  of,  314 
nutrient  vessels  of,  325 
osteomyelitis  of,  341 
periosteum  of,  325 
shaft  of,  325 

variations  in  length  of,  325 
Fenestra  ovalis,  46 

rotunda,  46 
Ferguson's  mode  of  dividing  palate 

muscles,  108 
Fibro-cartilage,  semilunar,  of  knee, 

.339 

triangular,  of  wrist,  418 
Fibula,  352 

fractures  of,  352 
Filiform  papillae  of  tongue,  102 
Filtering  angle  of  eyeball,  69 
Filum  terminale,  143 
Fimbriae  of  Fallopian  tube,  280 
Finger,  436 

abscess  of,  428 

amputation  of,  437 

avulsion  of,  436 

contraction  of,  430 

fractures  of,  436 

lymphatics  of,  43 1 

mallet,  436 

nerve-supply  of,  438 

pulp  of,  426 

synovial    sheaths     of    flexor 

tendons  of,  428 
theca*  of  tendons  of,  429 
wounds  of,  428 

Fissure   for  ductus  venosus,   228, 
229 


Fissure  for  obliterated    umbilical 
vein,  229 

Glaserian,  92 

longitudinal,  of  brain,  4 

longitudinal,  of  liver,  229 

of  anus,  297 

of  brain,  20 

of  liver,  228 

of  lung,  172 

of  Rolando,  4,  20 

of  Santorini,  43 

of  Sylvius,  4,  20 

portal,  229 

pterygo-maxillary,  97 

sphenoidal,  97 

spheno-maxillary,  97 

umbilical,  of  liver,  229 
Fistula,  branchial,  137 

faecal,  1 86,  268 

in  ano,  297 

perineal,  286 

salivary,  91 

umbilical,  186,  187 

urinary,  286,  186 

vesico-vaginal,  261 
Flat-foot,  369 
Floating  kidney,  243 

patella,  343 

Fold,  aryteno-epiglottic,  124 
,    gluteal,  299 

of  Douglas,  1 80 

of  ureter,  253 

sacro-genital,   253,    257,    275, 
283 

salpingo-pharyngeal,  109 

utero-sacral,  253 
Fontana,  spaces  of,  64 
Fontanelles,  n 

sagittal,  4 
Foot,  353 

abscess,  355-357 

amputation,  369 

arches,  354 

bones  of,  366 

deformities  of,  367 

dislocations  of,  367 

fasciae,  357 

flat,  369 

fractures,  366 

integuments,  355 

joints,  364 

lymphatics,  356 

nerves,  357 

surface  anatomy  of,  353 

vessels  of,  356 

wounds  of,  357,  361 
Foramen  caecum  of  medulla,  32 
of  tongue,  103 


454 


SURGICAL  ANATOMY 


Foramen  inferior  dental,  92 

infra-orbital,  4 

jugular,  39 

mastoid,  10 

mental,  5 

of  Key  and  Retzius,  31 

of  Majendie,  31,  24 

of  Monro,  24 

of  Winslow,  20 1 

parietal,  10 

sacro -sciatic,  304 

spheno-palatine,  99 

spinosum,  13 

supra-orbital,  54 
Forearm,  413 

amputation  of,  421 

bones,  416 

dislocations,  412 

fractures,  419 

integuments  of,  414 

luxations,  413 

lymphatics,  414 

muscles,  414 

nerves,  414 

surface  anatomy  of,  413 

vessels,  414 
Foreign  bodies  in  air-passages,  168 

in  ear,  43 

in  oesophagus,  132 
Formatio  reticularis,  33 
Fornix  of  conjunctiva,  57 

of  vagina,  278 
Fossa,  antecubital,  407 

anterior  of  skull,  12 
fracture  of,  15,  12 

canine,  85,  92 

coronoid,  408 

cranial,  12 

digital,  of  testicle,  271 

duodenal,  213 

glenoid,  92 

ileo-caecal,  219 

ileo-colic,  219 

iliac,  239 

infraclavicular,  375 

inguinal,  190 

intersigmoid,  225 

ischio-rectal,  289,  285 

middle,  of  skull,  12 

nasal,  75 

navicularis,  263 

obturator,  254,  312 

olecranon,  408 

of  Rosenmuller,  no 

ovarii,  281,  254 

pararectal,  254,  291 

paratrigonal,  260 

paravesical,  253 


Fossa,  patellaris,  69 

pelvic,  253 

posterior,  of  skull,  14 

pterygo-maxillary,  96 

pyriform,  no 

radial,  409 

retrocolic,  219 

retro-ureteric,  260 

spheno-maxillary,  99 

supraclavicular,  114 

supraclavicular  minor,  113 

supratonsillar,  108 

trochanteric,  300    •.  . 

zygomatic,  96  , 

Fourth  ventricle,  3 1 ,  24 
Fovea  centralis  retinae,  69 
Fracture.     See  Various  bones 

by  contre-coup,  1 1 

dislocation  of  vertebrae,  142 
Frenulum  linguae,  103 

penis,  266 

Frenum  epiglottidis,  103 
Frontal  lobes  of  cerebrum,  20 

sinus,  82,  10 

empyema  of,  83 
fracture  of,  83 
Fronto-nasal  duct,  83,  78 

process,  80 
Fundus  of  gall-bladder,  233 

of  stomach,  204 

of  uterus,  275 

Fungiform  papillae  of  tongue,  103 
Funicular  process  of  peritoneum, 

196 
hernia  into,  197 

hydrocele,  197 

Gaertner,  duct  of,  282 
Galactocele,  160 
Gall-bladder,  233 

distension  of,  234 

fund  us  of,  233 

nerves  of,  235 

operations  on,  234 

surface  anatomy  of,  233 

ulceration  of,  234 
Gall-stones,  intestinal  obstruction 

caused  by,  234 
Ganglion  at  wrist,  431 

Gasserian,  13,  36 

lenticular,  36 

Meckel's,  87,  36 

otic,  36 

Gangrene,  bowel,  248 
Gasserian  ganglion,  removal  of  : 
Hartley  Krause,  99 
Macewen,  13 
Rose,  99 


INDEX 


455 


Gastrectasis,  atonic,  206 

stenotic,  206 
GastreAomy,  208 
Gastric  dilatation  associated  with 

movable  kidney,  243 
Gastric  ulcer,  203 
Gastro-jejunostomy,  209 
Gastro-colic  omentum,  201,  200 

-hepatic  omentum,  201,  203, 

230 

-splenic  omentum,  204,  237 
Gastrostomy,  207 
Gastrotomy,  208 
Generative    organs,   development 

of,  266,  279 
female,  275 
male,  265 
Genu  valgum,  326 
varum,  327,  352 

osteotomy  for,  327,  352 
recurvatum,  338 
Giraldes,  organ  of,  271 
Girdle,  shoulder,  377 
Glabella,  3 
Gladiolus,  151 

Glands  of  Montgomery,  157 
Glandulae  concatenatae,  137 
Glans  penis,  265 
Glaserian  fissure,  92 
Glaucoma,  64,  69 
Glaucomatous  cup,  64,  68 
Glenoid  cavity,  scapula,  384 

fossa,  lower  jaw,  92 
Glisson's  capsule,  228 
Globular  process,  101 
Glossitis,  104 

Glosso-epiglottidean  folds,  102 
Glottis,  oedema  of,  124 
respiratoria,  125 
vocalis,  125 
Gluteal  abscess,  301 
aneurism,  302 
bursae,  301,  302 
fascia,  301 
fold,  299 
integuments,  300 
region,  299 

nerves  of,  304 
surface  anatomy  of,  299 
vessels  of,  302 
wounds  of,  304 
Goitre,  130 
Goll,  columns  of,  32 
Gosselin's  fracture,  352 
Gower's  comma  tract,  33 
Great  omentum,  200 

sacro-sciatic  foramen,  304 
transverse  sinus,  163 


Great  trochanter,  299,  314 
Grey  matter  of  cord,  33 
Gritti's  amputation,  344 
Gubernaculum  testis,  195 
Gudden's  commissure,  35 
Gums,  ioj 

Haemarthrosis  of  knee,  337 
Haematocele,  272 
Haematoma  of  scalp,  8 

of  pinna,  42 
Haemoptysis,  173 
Haemorrhage,  cerebral,  29 

extradural,  26 

from  frenum  linguae,  103 

from  tongue,  103 

from  tonsil,  108 

in  laminectomy,  149 

in  lithotomy,  288 

into  chorioid,  67 

into  internal  capsule,  23 

into  vitreous,  71 

meningeal,  17,  18 

subconjunctival,  57 
Haemorrhoids,  294,  231 
Haemosalpingitis,  281 
Haemothorax,  173 
Hallux  rigidus,  369 

valgus,  365 
'Hammer  toe,  369 
Hamular  process,  107 
j    Hand,  421 

amputation  of,  435 

creases  of,  423 

fasciae  of,  426 

lymphatics  of,  425 

skin  of,  425,  426 

surface  anatomy  of,  421 

synovial  sheaths  of,  428 

synovitis  of,  429 

vessels  of,  425 

wounds  of,  428 
Hanging,  146 
Hard  palate,  106 
Hare-lip,  88,  101,  106 

median,  101 
Head  (Section  I.),  affections  of,  I 

asymmetry  of,  i 
Heart,  164 

displacements  of,  165 

valves  of,  164 

wounds  of,  165 
Heel,  integument  of,  356 
Helicoidal    fractures    of    Leriche, 

326 

Hemianopsia,  35 
Hemiplegia,  23 
Hepatectomy,  232- 


456 


SURGICAL  ANATOMY 


Hepatic  artery,  231 

duct,  233 

flexure  of  colon,  223 

veins,  232 
Hepato-ptosis,  227 
Hepatotomy,  228 
Hermaphroditism,  pseudo,  267 
Hernia,  caecal,  218 

complete,  191 

conditions  resembling  femoral, 

305 

conditions  resembling  in- 
guinal, 197,  272,  273 

congenital,  197 

coverings  of,  190,  193 

diagnosis,  mistakes  in,  194, 
202,  307 

diaphragmatic,  199 

direct,  190 

encysted  infantile,  197 

femoral,  191 

infantile,  197 

inguinal,  187 

into  funicular  process,  197 

intraparietal,  182 

labial,  191 

Littre's,  198 

lumbar,  199 

mesenteric,  214 

oblique,  190 

obturator,  194 

of  bladder,  261- 

of  lung,  1 70 

of  muscle,  324 

of  pancreas,  237 

omental,  202 

parts  concerned  in  inguinal, 
viewed  from  behind,  187 
et  seq. 

perineal,  199 

pudendal,  199 

radical  cure  of  femoral,  199 
of  inguinal,  198 

rare  forms  of,  199 

retroperitoneal,  213 

Richter's,  198 

sciatic,  199,  304 

scrotal,  191 

strangulated,  198 
relief  of,  198 

taxis,  194 

umbilical,  186 

vaginal,  279 

ventral,  178,  221 
Herniotomy,  193,  195 
Herophili  torcular,  26 
Herpes  zoster,  155,  167 
Hesselbach's  triangle,  189 


Hey's  amputation,  370 

dislocation,  437 
Hiatus  semilunaris,  78 
Highmore,  antrum  of,  83 

empyema  of,  84 
Hilton's  law,  399 

method  of  opening  abscesses, 

9i 

white  line,  293 
Hilum  of  kidney,  242 

lung,  173 

spleen,  237 
Hip,  299 

amputation  at,  322 

dislocations  of,  317,  321 

disease,  320,  313 

excision  of,  322 

fractures  of,  316 

hysterical,  316 

joint,  312 

movements  of,  315 

nerve-supply,  316 

region,  299 

surface  anatomy  of,  299 

synovial  membrane  of,  316 

vessels  of,  316 
Hippocratic  hand,  425 
Hodgkin's  disease,  spleen  in,  238 
Holden's  line  of  thigh,  305 

of  face,  37 
Hordeolum,  55 
Horseshoe  kidney,  242 
Hourglass  stomach,  207 
Housemaid's  knee,  330 
Houston's  valves  of  rectum,  290 
Humerus,  399 

anatomical  neck  of,  399,  400 

development  of,  400 

dislocations  of,  385 

epiphyses  of,  400 

fractures  of,  400 

lower  extremity  of,  408,  402 

musculo-spiral  groove  of,  399 

nutrient  artery  of  397,  402 
foramen  of,  399 

shaft  of,  400 

surgical  affections  of,  402 

neck  of,  399 
Humour,  aqueous,  69 

vitreous,  70 
Hunter's  canal,  323 
Hutchinson  teeth,  96 
Hyaloid  artery,  71 

canal,  71 

membrane,  70 
Hydatid  cyst,  233 

of  Morgagni,  271,  282 
Hydrencephalocele,  19 


INDEX 


457 


Hydrocele,  271,  272 

bilocular,  197 

congenital,  197 

encysted  of  cord,  197 

infantile,  197 

of  canal  of  Nuck,  283 

of  neck,  137 
Hydrocephalus,  25 
Hydronephrosis,  244 
Hydrosalpingitis,  281 
Hygroma  of  neck,  137 
Hymen,  277 
Hyoid  bone,  122,  112 

fracture  of,  122 
Hypermetropia,  64 
Hypertrophy  of  bladder,  259 

of  prostate,  269 

Hypochondriac    region    of    abdo- 
men, 177 

Hypogastric  region,  177 
Hypopyon,  64 
Hypospadias,  266 
Hypothenar  eminence,  426 
Hysterectomy,  276 
Hysterical  hip,  316 

Ileo-caecal  fossa,  219 

intussusception,  222 
valve,  221 
Ileo-colic  fossa,  219 

intussusception,  222 
Ileum,  214 
Iliac  abscess,  241 
colon,  224 
fascia,  240,  191 
fossa,  239 
region,  177 
spines,  299 
vessels,  256 
Ilio-pectineal  line,  188 

tibial  band,  301,  308 
Imperforate  anus,  296 
Incontinence  of  faeces,  295 
urine,  297 

Incisor,  supernumerary,  107 
Inequality  in  length  of  limbs,  325 
Infantile  hernia,  197 

hydrocele,  197 
Inferior  maxilla,  92 

deformities  of,  92 
dislocations  of,  93 
excision  of,  94 
fracture  of,  92 
subluxation  of,  93 
Infraclavicular  fossa,  375 
hyoid  region,  123 
mesocolic     compartment    of 
abdomen,  202,  212 


Infra-orbital  foramen,  4 
patellar  bursa,  330 
pad  of  fat,  330 
Infundibuliform  fascia,  189 
Infundibulum  of   Fallopian  tube, 

280 

of  nose,  78 
Inguinal  canal,  187 
colotomy,  225 
fossae,  190 
hernia,  190 

affections    resembling, 

197,  272,  273,  305 
radical  cure  of ,  198 
lymphatics,  306 
region,  187 

viewed  from  behind,  188 
Inion,  3 

Intercolumnar  fascia,  191 
Intercostal  membranes,  1 54 
muscles,  154 
nerves,  155,  154 
neuralgia,  155 
spaces,  153 
vessels,  154 
Interrnuscular  septa  of  arm,  396 

of  thigh,  323 

Internal  abdominal  ring,  189 
capsule,  22 
ear,  54 

strangulation  of  intestine,  217 
table  of  skull,  9 

Interosseous  membrane  of  arm,  417 
of  leg,  437 

Interparietal  bone,  4 
Intersigmoid  fossa,  225 
Intervertebral  disc,  141 
Intestinal  obstruction,    214,    217, 

218 

Intestine,  development  of,  186,  218 
large,  217 

characteristics  of,  226 
functions  of,  226 
lymphatics  of,  226 
nerves  of,  226 
operations  on,  225 
stricture  of,  226 
vessels  of,  226 
small,  arrangement  of,  in  ab 

domen,  215 
determination    of    upper 

end  of  loop  of,  214 
diseases  of,  215 
diverticula  of,  217 
identification  of,  215 
length  of,  214 
lymphatics  of,  216 
nerves  of,  217 


45* 


SURGICAL  ANATOMY 


Intestine,    small,    operations    on, 

216 

strangulation  of,  214 
stricture  of,  215 
ulcers  of,  215 
vessels  of,  216 
wounds  of,  216 
Intra-capsular  fracture  of  femur, 

316 

ligaments  of  eye,  62 
-coracoid        dislocation        of 

shoulder,  386 
-cranial  pressure,  25 
sinuses,  14 

-mammary  abscess,  160 
-ocular  tension,  69 
-pelvic  cellulitis,  281 
Intussusception,  222,  217 
ileo-caecal,  222 
ileo-colic,  222 
Inversion  of  testicle,  274 
Iridectomy,  66 
Irideremia,  66 
Irido-cyclitis,  67 
Iris,  65 

coloboma  of,  66 
injuries  of,  66 
Iritis,  67 
Ischio-rectal  abscess,  297 

fossa,  289,  285 
Island  of  Reil,  22 
Isthmus  of  Fallopian  tube,  280 
of  fauces,  106 
of  thyroid,  130 
Iter  ad  antrum,  48 

relation  of  external  semi- 
circular canal  to,  48 
relation   of    facial    canal 

to,  48 
relation  of  temporo-sphe- 

noidal  lobe  to,  48 
Iter  chordae  anterius,  45 
posterius,  45 

Jacksonian  epilepsy,  34 
Jacob's  ulcer.      See  Rodent  ulcer 
Jaundice   associated    with    mov- 
able kidney,  243 
Jaw,  lower,  92 
upper,  88 
Jejunum,  214 

Joints.      See     Various      articula- 
tions 

Jordan's  amputation,  322 
Jugular  vein,  internal,  135 
air  in,  135 
thrombosis  of,  135 
wounds  of,  135 


Keratitis,  65 
Keratoconus,  64 
Kidney,  242 

abnormalities  of,  242 

abscess  of,  245 

adipose  capsule  of,  243 

calculi,  245 

calyces,  245 

capsule,  proper,  of,  244 

fibrous  capsule  of,  243 

floating,  243 

hilum  of,  242 

horseshoe,  242 

infection,  mode  of,  245 

injuries  of,  245 

movable,  243 

nerve-supply  of,  244 

operations  on,  246 

pelvis  of,  245 

position  of,  242 

relations  of,  244 

to  twelfth  rib,  244 

supernumerary,  242 

supporting  mechanism,  243 

surgical,  245 

tuberculosis  of,  245 

vessels  of,  244 
Knee,  328 

bursae  about,  330 

fractures  about,  337,  341 

housemaid's,  330 

nbro-cartilages  of,  339 

integuments  of,  329 

joint,     amputation     through, 

344 

capsule  of,  335,  338 
disease  of,  343 
dislocations  of,  344 
excision  of,  343 
flexion  of,  333 
nerves  of,  343 
subluxation  of,  343 
synovial    membrane    of, 

339 
vessels  of,  343 

nerves  of,  329 

surface  anatomy  of,  328 

vessels  of,  329 

of  sigmoid  sinus,  50 
Knock-knee,  326 
Kocher's  operation  on  nose,  80 
Kraske's  operation,  296 
Kyphosis,  140 

Labia  majora,  284 
Labial  hernia,  191 
Labio-glossal  paralysis,  41 
Labyrinth  of  ear,  54 


INDEX 


459 


Lachrymal  abscess,  59 

apparatus,  58 

cairiil,  59 

canaliculi,  59 

caruncle,  56 

gland,  58 

nerve  of,  58 

puncta,  59 

sac,  59 
Lacteals,  216 
Lactiferous  ducts,  156 
Lacuna  magna,  264 
Lacus  lachrymalis,  56 
Lagophthalmos,  56 
Lambda,  2 
Lambdoidal  suture,  2 
Lamina,  basalis,  67 

chorio-capillaris,  67 

fusca,  67 

Laminectomy,  149 
Large  intestine.     See  Caecum, 

Colon,  Rectum 
Laryngeal  glands,  124 

pharynx,  no 

saccule,  125 
Laryngitis,  124 
Laryngoscopy,  126 
Laryngotomy,  126,  112 
Larynx,  123 

excision  of,  127 

foreign  matter  in,  125,  126 

fracture  of,  126 

lymphatics  of,  125 

mucous  membrane  of,  124 

nerves  of,  124 

new  growths  of,  124 

relations  of,  124 

vessels  of,  125 

ventricle  of,  125 

vestibule  of,  125 

Lateral  curvature   of  spine.     See 
Scoliosis 

lithotomy,  287 

sinuses,  27,  4 

ventricles,  24 

tapping  of,  25 
Leg,  345 

amputation  of,  353 

bones  of,  351 

fasciae  of,  347 

fractures  of,  351,  352 

integuments  of,  346 

lymphatics  of,  356 

muscles  of,  347,  350 

nerves  of,  371 

rickets  of,  351 

surface  anatomy  of,  345 

varicose  veins  of,  346 


Leg,  vessels  of,  346 
Lens,  69 

capsule  of,  70 

equator  of,  70 

poles  of,  70 

suspensory    ligament   of,    66, 

70,  71 

Lenticular  nucleus,  22,  23 
Leptomeningitis,  19 
Leriche,     helicoidal    fracture    of, 

326 
Lesser  curvature  of  stomach,  203 

peritoneal  sac,  201 

trochanter,  314 
Leucoplakia  of  tongue,  103 
Leukaemic  enlargement  of  spleen, 

238 

Lieberkiihn's  glands,  215 
Lienculi,  237 
Ligament.     See  various  regions 

annular,  of  ankle,  358 

of    wrist,    423,   427, 

43i 

Bigelow's,  315 
bladder,  257 
broad,  279 

calcaneo-metatarsal,  357 
calcaneo-scaphoid,  365 
capsular  of  hip,  315 
cervical  of  femur,  314 
check,  62 
conoid,  380,  383 
coraco-acromial,  383 
coraco-clavicular,  383 
coraco-humeral,  385 
coronary,  liver,  230 
cotyloid,  313 
crucial,  of  knee,  339 
cutaneous  phalangeal,  of  Cle- 

land,  426 

falciform,  193,  228 
Gimbernat's,  188 
glenoid,  384,  436 
gleno-humeral,  385 
hepato-colic,  223 
ilio-femoral,  315 
ilio-lumbar,  240 
ilio-pectineal,  309 
interclavicular,  378 
intracapsular,  62 
ischio-femoral,  315 
lateral,  of  rectum,  292 
lieno-renal,  237 
Lisfranc's,  365,  370 
oblique,  417 
of  ovary,  281 
orbicular,  410,  409 
of  Treitz,  211 


46o 


SURGICAL  ANATOMY 


Ligament  of  Wins  low,  338 

peritoneal,  200 

phreno-colic,  224 

plantar,  364 

Poupart's,  1 80 

pterygo-maxillary,  93,  101 

pterygo-spinous,  96 

pubo-femoral,  of  hip,  315 

rectal,  292 

rhomboid,  378 

round,  of  liver,  230,  186 
of  uterus,  283 

sacro-genital,  253 

sacro-sciatic,  304 

spheno-maxillary,  93 

spinal,  142 

stylo-maxillary,  90,  93 

suspensory,  of  breast,  156 
of  Cooper,  156 
of  lens,  66,  70,  71 
of  Lockwood,  62 
of  ovary,  280,  281 
of  penis,  265 
of  tarsi,  56 

thyro-arytenoid,  125 

transverse,  of  ankle,  361 
of  hip,  313 
of  humerus,  385 
of  knee,  339 
of  metacarpus,  436 

trapezoid,  379 

triangular,  286 

Y-shaped  hip,  315 
Ligamenta  alaria,  339 

brevia,  430 
Ligamentum  latum  pulmonis,  169 

mucosum,  339 

nuchae,  114 

patellae,  336 

pectinatum  iridis,  64 

teres,  314 

Lighterman's  bottom,  302 
Line,  Holden's,  of  face,  37 

of  thigh,  305 

ilio-pectineal,  188 

Nelaton's,  300 

of  pleural  reflection,  169 

white,  of  anus,  293 

of  pelvis,  25  i 
Linea  alba,  178 

aspera  of  femur,  325 

semilunaris,  179 
Lineae  albicantes,  177 

transversae,  178,  179 
Lingual  tonsil,  103 

triangle,  122 
Lipoma  nasi,  74 
Lips,  100 


Lips,  lymphatics  of,  100 

nerves  of,  100 

surgical  affections  of,  TOO 

vessels  of,  100 
Lisfranc's  amputation,  369 
Lister's  amputation  of  knee,  344 
Litholapaxy,  262 
Lithotomy,  perineal,  287 

suprapubic,  262 
Lithotrity,  262 
Littre's  hernia,  198 

operation,  296 
Liver,  227 

abscess  of,  232 

capsule  of,  228 

caudate  lobe  of,  229 

channels  of  infection  of,  232 

fixation  of,  230 

hydatids  of,  233 

injuries  to,  232 

in  pyaemia,  232 

ligaments  of,  230 

lymphatics  of,  232 

nerves  of,  232 

nutmeg,  231 

operations  on,  232 

peritoneum  of,  228 

ptosis  of,  231 

quadratic  lobe  of,  228 

relations  of,  228 

Riedel's  lobe  of,  228 

Spigelian  lobe  of,  228 

surface  anatomy  of,  228 
relations  of,  227 

tight-lacing,  effects  of,  on,  228 

tumours  of,  232 

uncovered  area  of,  228 

vessels  of,  231 
Lobes  of  brain,  20 

of  liver,  228 

Localization,  cerebral,  20 
Lockjaw,  or  trismus,  93 
Long  bones,  surgical  affections  of, 

34i 
Longitudinal  fissure,  4 

sinus,  26,  4 
Lordosis,  141 
Lower  jaw,  92 

articulation  of,  93 

condyle  of,  92 

congenital  defects  of,  92 

dislocation  of,  93 

excision  of,  94 

fractures  of,  92 

nerves  of,  94 

subluxation  of,  93 

surgical  affections  of,  93 

vessels  of,  94 


INDEX 


461 


Lower  limb,  length  of,  325 
Ludwig's  angina,  102,  122 
Lumbago,  141 
Lumbar  abscess,  241 

aponeurosis,  239 

caries,  141 

colotomy,  225 

fasciae,  239 

hernia,  199 

puncture,  144 

region,  239,  177 

spine,  141,  142 

injuries  to,  142 
Lungs,  172 

abscess  of,  173 

apex  of,  172 

bleeding  from,  173 

cavities  in,  174 

collapse  of,  170 

elasticity  of,  170 

emboli  of,  173,  174 

extent  of,  in  root  of  neck,  113 

fissures  of,  172 

hernia  of,  170 

hilum  of,  173 

incisura  of,  172 

lobes  of,  172 

nerves  of,  173 

relations  of,  to  chest  wall,  172 

root  of,  173 

rupture  of,  173 

surgery  of,  173,  174 

tumours  of,  173 

vessels  of,  173 

wounds  of,  172,  173 
Lupus,  85 

Luschka's  tonsil,  no 
Lymphatics.     See  Various  regions 

Macrocheilia,  100 
Macroglossia,  104 
Macrostoma,  88,  101 
Macrotia,  42 
Macula  lutea,  69 
Magendie,  foramen  of,  31,  24 
Malar  bone,  fracture  of,  89 
Malignant  pustule,  85 
Malleoli,  fracture  of,  341 
Mallet  finger,  436 
Mamma,  156 

abnormalities  of,  160 

abscess  of,  160,  156 

areola  of,  157 

capsule  of,  156 

carcinoma  of,  157  et  seq. 

development  of,  156 

examination  of,  160 

incision  of,  156 


Mamma,  inflammation  of,  160 

lymphatics  of,  157 

nerves  of,  160 

nipple,  156 

relations  of,  156 

sarcoma  of,  159 

skin  of,  157 

supernumerary,  306 

suspensory  ligaments  of,  156 

tumours  of,  159 

vessels  of,  157 
Manubrium,  151 
Mastitis,  160 
Mastoid  abscess,  49 

aditus,  48 

antrum,  48 

cells,  48 

cholesteatoma,  54 

lining  of,  48 

process,  53 

pus,  modes  of  escape  from,  53 

relation  of  facial  canal  to,  53 
of  sinus  to,  50 

suprameatal  triangle,  52 

surgery  of,  52 

tegmen  of,  48 

vein,  10,  28 
Mastoidectomy,  52 
Mastoiditis,  49 

sequelae,  50 

cerebellar  abscess,  5 1 
cerebral  abscess,  5  i 
facial  paralysis,  52 
meningitis,  51 
sigmoid      sinus     throm- 
bosis, 51 

Masto-squamosal  suture,  53 
Maxilla.     See  Inferior  and  Supe- 
rior 

McBurney's  point,  221 
Meatal  point,  3 
Meatus  auditorius,  43 

of  nose,  78 

urinarius,  264 
Meckel's  diverticulum,  186,  217 

ganglion,  87,  36 
Median  hare-lip,  101 

lithotomy,  288 
Mediastinal  abscess,  161 

aneurism,  161 

lymphatic  glands,  155 

pleura,  169 

tumours,  161 

Mediastinum,  160 

testis,  272 

Mediocarpal  joint,  433 
Mediotarsal  joint,  364 
Medulla  oblongata,  31 


462 


SURGICAL  ANATOMY 


Megacephalic  skull,  I 
Meibomian  glands,  54 
Meissner's  plexus,  217 
Membrana  flaccida,  45 

tympani,  44 
Membrane,  costo-coracoid,  389 

crico-thyroid,  126 

interosseous,  of  forearm,  417 
of  leg,  347 

obturator,  312 

of  brain,  16 

of  Bruch,  67 

of  cord,  144 

of  Descemet,  64 

Schneiderian,  76 

Shrapnell's,  45 

thyro-hyoid,  123 

tympanic,  44 
Membranous  urethra,  263 
Meniere's  disease,  54 
Meningeal  haemorrhage,  13,  17,  18 

vessels,  26 

Meningitis,  cerebral,  19 
spinal,  144 
Meningocele,  cranial,  3,  19,  76 

spinal,  145 

Meningo-encephalocele,  19 
Meningo-myelocele,  145 
Mental  foramen,  5 
Mesencephalon,  30 
Mesenteric  glands,  217 
hernia,  214 
Mesentery,  213,  195,  201 

apertures  in,  214 

attachment  of,  213 

cysts  of,  217 

diseases  of,  217 

length  of,  214 

prolapse  of,  214 
Mesoappendix,  219 
Mesocolon,  transverse,  201,  224 
Mesognathion,  107 
Mesometrium,  283 
Mesonephron,  243 
Mesosalpinx,  280 
Mesovarium,  281 

Metacarpal  bones,  fracture  of,  436 
Metacarpo-phalangeal  joints,  dis- 
location of,  436 
Metatarsal  bones,  367 
Metatarso-phalangeal   joints,    dis- 
location of,  436 

Metatarsus,  amputation  of,  369 
Metritis,  276 
Microcephalic  skull,  I 
Microstoma,  88,  101 
Microtia,  42 
Micturition  centre,  260 


Middle  ear,  45 

fossa  of  skull,  12 

meningeal  artery,  trephining 

for,  26 

Midcarpal  joint,  433 
|   Midtarsal  joint,  364 

amputation  through,  370 
Miliary  aneurism  of  Charcot,  29 
Milk-ducts,  156 
Miner's  elbow,  408 
Mitral  valve,  165 
Monro,  foramen  of,  24 
Montgomery's  glands,  157 
Morbus  coxae,  320 
Morgagni,  columns  of,  293 

hydatid,  of,  271,  282 
Motor  centres  of  cortex,  20 

speech  centre,  20 

tracts  in  cord,  33 
Mouth,  100 

vestibule  of,  100 
Movable  kidney,  243 
Mucocele,  82 
Mucous  colitis,  220 

polypus  of  nose,  77 
Mule's  operation,  67 
Miiller,  ducts  of,  279,  266 

muscle  of,  61 
Mumps,  91 
Muscae  volitantes,  71 
Muscle  (see  Various  regions)  : 

adductors,  311,  323 

back  of  neck,  1 19 

biceps,  396 

ciliary,  66 

compressor  urethras,  263 

constrictors  of  pharynx,  1 10, 

122 

cremaster,  182 
deltoid,  382 
digastric,  120 
epitrochleo-anconeus,  408 
flexor  carpi  ulnaris,  422 
gemelli,  301 
glutei,  301 

hyo-glossus,  121,  122 
ilio-psoas,  311 
intercostal,  154 
interossei,  425 
latissimus  dorsi,  377,  381 
lumbricales,  430 
mylo-hyoid,  120,  122 
obturator,  301 
occipito-frontalis,  5 
ocular,  59 
of  Treitz,  211 
omo-hyoid,  120 
orbitalis,  of  Miiller,  61 


INDEX 


463 


Muscle,  palatal,  107 

palmaris  longus,  421 

pectoralis  major,  388 
minor,  389 

plantaris,  349 

platysma  myoides,  114 

prevertebral,  119 

pterygoid,  98 

pyriformis,  301 

pyramid  alls,  180 

quadriceps  extensor,  324 

rectus  abdominis,  179 

scalene,  119 
Musculo-spiral  groove,  399 

nerve,  injury  to,  401 
Myelocele,  145 
Myoma  uteri,  276 
Myopia,  64 
Myxoedema,  131 

Nails,  425 

Nares,  anterior,  75 

plugging,  79 

operations  on,  80 

posterior,  75 
Nasal  asthma,  80 

bones,  75 

fracture  of,  75 

douche,  76 

duct,  78,  59 

exploration  of,  80 

fossa,  75 

mucous  membrane,  76 
olfactory  portion,  76 
respiratory  portion,  76 
roof  of,  75 

lymphatics,  76 

obstruction,  80 

operations,  80 

polypus,  77,  80 

septum,  75 

perforation  of,  75 

tumours,  77 
Nasion,  3 

Naso-pharynx,  109 
Neck,  112 

abscess  of,  1 16 

aneurism  of,  138,  139 

cysts  of,  137 

development  of,  137 

fasciae  of,  114 

fistulae  of,  137 

hydrocele  of,  137 

integuments  of,  114 

lung  in,  113,  136 

lymphatics  of,  132,  133 

middle  line  of,  112 

muscles  of,  117 


Neck,  nerves  of,  117 

ribs  in,  137 

surface  anatomy  of,  112 

triangles  of,  112 

wounds  of,  123,  135 
Nelaton's  line,  300 
Necrosis,  of  bones  of  vault,  9 

of  long  bones,  342 
Nephrectomy,  245 
Nephrolithotomy,  245 
Nephropexy,  246 
Nephrorrhaphy,  246 
Nephrotomy,  245 
Nerve-stretching,  304 
Nerve.     See  Various  regions 

alderman's,  39 

anterior  crural,  311,  372 
tibial,  348 

Arnold's,  39 

auditory,  39 

auricular,  of  vagus,  39 

auriculo-temporal,  36 

Bell's,  381 

cervical  sympathetic,  133 

chorda  tympani,  38,  45 

ciliary,  72 

circumflex,  399 

cranial,  35 

descendens  noni,  132 

eighth,  39 

external  respiratory,  of  Bell, 
38i 

eleventh,  41 

facial,  38,  53,  86 

fifth,  36,  60,  87 

first,  35 

fourth,  35,  60 

genito-crural,  311 

glosso-pharyngeal,  39 

great  auricular,  118 
petrosal,  38 
sciatic,  323,  372 

gustatory,  36,  101 

hypoglossal,  41,  104 

inferior  dental,  37,  38,  52,  98 
maxillary,  36 

infra-orbital,  37 

intercostal,  155 

internal  cutaneous,  397,  414 

Jacobson's,  47 

laryngeal,  recurrent,  40,  125 

lingual,  99,  37,  101 

long  saphenous,  309,  323 

median,  439,  397,  415 

mental,  37 

musculo-cutaneous,  348,  414 

musculo-spiral,  439,  397,  414 

ninth,  39 


464 


SURGICAL  ANATOMY 


Nerve,  obturator,  312,  371 
olfactory,  35 
ophthalmic,  36,  72 
optic,  35 
palatine,  106 
peroneal,  374 
phrenic,  167 
plantar,  373 

pneumogastric,  39,  175,  206 
popliteal,  331 
posterior  thoracic,  381 

tibial,  349 
pudic,  288 

recurrent  laryngeal,  40 
respiratory,  of  Bell,  381 
sciatic,  great,  331,  302 

small,  302 
seventh,  38 
sixth,  38,  60 
small  occipital,  117 
spinal  accessory,  41,  113 
superficial  cervical,  118 
superior  maxillary,  36 
supraclavicular,  377 
supra-orbital,  37 
sympathetic,  61,  72,  133 
tenth,  39 
third,  60,  35,  72 
tibial,  372 
trigeminal,  36 
twelfth,  41,  104 
ulnar,  441,  397,  415 
vagus,  39,  132 
Vidian,  81 
Nerve,    artificial    anastomosis, 

39 

points  of  exit  from  vertebral 
canal,  147 

supply  of  lower  limb,  371 

supply  of  upper  limb,  438 
Neuralgia,  trigeminal,  37 
Night-startings,  343 
Nipple,  1 60 

supernumerary,  160 
Nose,  affections  of,  74 

accessory  sinuses  of,  80 

alae  of,  74 

atrium  of,  76 

bleeding  from,  77 

cartilaginous  portion,  74, 

75 

foreign  bodies  in,  80 
lymphatics  of,  76,  77 
meati  of,  78 
nerves  of,  74,  80 
outer  wall  of,  76 
skin  of,  74 
ulceration  of,  74 


Nose,  vessels  of,  77,  74 

vestibule  of,  76 

wounds  of,  74 
Notch,  cotyloid,  313 

of  Rivini,  45 
Nuck,  canal  of,  198,  283 

hernia  into,  198,  283 

hydrocele  of,  283 
Nuclei  of  medulla,  32 
Nutmeg  liver,  231 

Oblique  inguinal  hernia,  190 

muscles  of  abdomen,  181 

of  orbit,  60 
Obturator  canal,  312,  194 

fascia,  251 

fossa,  254,  312 

hernia,  312 

herniotomy,  195 

membrane,  312 

or  thyroid  dislocation,  318 

region,  312 

vessels  of,  312 
Occipital  lobes  of  brain,  21 

protuberance,  3 

sutures,  3 

triangle,  136 

Occipito-frontalis  aponeurosis,  5 
Ocular  apparatus,  54 
CEdema  of  eyelids,  55 

of  glottis,  124 

of  scrotum,  274 
(Esophageal  bougie,  176 

groove  of  liver,  228 

plexus,  175 
CEsophagectomy,  132 
CEsophagostomy,  132 
CEsophagotomy,  132 
CEsophagus,   cervical  segment  of, 

131 

foreign  bodies  in,  132 
operations  on,  132 
relations  of,  131,  174 
stricture  of,  132,  174 
thoracic  segment  of,  174 

Olecranon,  bursa  over,  408 
fossa,  408 
process,  409 
fracture  of,  412 
relation  of,  to  condyles,  405 

Olive  of  medulla,  32 

Omental  hernia,  202 
sac,  202 

Omentum,  functions  of,  202,  203 

in  hernia,  202 
gastro-splenic,  204,  237 
great     or     gastro-colic,     200, 


INDEX 


465 


Omentum,  lesser  or  gastro-hepatic, 

201,  203,  230 
OnychijS,,  425 

Ophthalmia,  sympathetic,  67 
Optic  atrophy,  68 

commissure,  35 

disc,  68 

nerve,  35 

neuritis,  68 

thalamus,  23 
Ora  serrata,  68 
Orbiculus  ciliaris,  66 
Orbit,  abscess  of,  61 

aneurism  of,  61 

fracture  of,  73 

movements  of,  60 

muscles  of,  60 

nerves  of,  60 

paralysis  of,  61 

tumours  of,  61 

vessels  of,  61 

wounds  of,  54,  73 
Orbital  cavity,  73 

tumours  of,  73 
wounds  of,  73 
Orchitis,  273 
Organ  of  Giraldes,  271 

of  Rosenmuller,  282 
Os  calcis,  366 

disease  of,  366 
dislocation  of,  366 
fracture  of,  366 

epactal,  3 

innominate,  249 

magnum,  434 

trigonum  tarsi,  362 

triquetrum,  1 1 
Ossicles,  53 

Osteomyelitis  of  long  bones,  341 
Ostia  of  accessory  sinuses,  78 
Othaematoma,  42 
Otitis  media,  47 
Ovarian  cyst,  282 

nmbria,  280 
Ovariotomy,  282 
Ovary,  281 

bursa  of,  280 

fossa  of,  281 

hernia  of,  282 

ligament  of,  280 

lymphatics  of,  282 

mesovarium  of,  281 

nerves  of,  282 

palpation  of,  282 

peritoneum  covering,  282 

prolapse  of,  282 

relations  of,  282 

suspensory  ligament  of,  281 


Ovary,  tumours  of,  282 

vessels  of,  282 
Ozcena,  76 

Pacchionian  bodies,  6,  10 

Pachy  meningitis,  19 

Pacinian  corpuscles,  357,  426 

Pain  referred,  155,  184,  206,  221, 
224,  233,  235,  245,  260,  268, 
273,  288,  295,  302,  316,  320, 


345.  357 
>alate,  106 


arch  of,  106,  107 

cleft,  107 

hard,  106 

muco-periosteum  of,  106 

muscles  of,  107 

nerves  of,  107 

soft,  1 06 

vessels  of,  107 
Palatal  crest,  106 
Palatine  canals,  106 
Palm,  abscess  of,  427 

central  compartment  of,  427 

creases  of,  423 

deep  compartment  of,  427 

skin  of,  426 

synovial  sheaths  of,  428 
Palmar  arches,  430 

fascia,  426 

Dupuytren's  contraction 
of,  427 

vessels,  423 

Pampiniform  plexus,  272 
Pancreas,  235 

access  to,  236 

cyst  of,  236 

ducts  of,  236 

functions  of,  236 

hernia  of,  237 

lesser,  235 

lymphatics  of,  236 

nerves  of,  236 

relations  of,  235 

surgery  of,  236 

tuber  omentale  of,  236 

uncinate  process  of,  235 

vessels  of,  236 
Pancreatic     diabetes,      operation 

for,  237 

Pancreatitis,   suppuration   follow- 
ing, 236 
Panniculus    adiposus    abdominis, 

178 

Pannus,  65 

Papilla  of  duodenum,  211,  234 
Papillae  of  tongue,  102,  103 
Paracentesis  pericardii,  164 

30 


466 


SURGICAL  ANATOMY 


Paracentesis  thoracis,  153 

tympani,  45 

ventricles  of  brain,  25 
Paradidymis,  271 
Parallel  fissure,  21 
Paralysis.    See  Various  nerves  and    j 
regions 

bulbar,  41 

Duchenne's,  41 

Erb's  brachial,  442 
Parametritis,  276 
Parametrium,  284 
Paraphimosis,  266 
Pararectal  fossa,  254,  291 
Parathyroid  bodies,  131 
Para-umbilical  veins,  179 
Paravesical  fossa,  253 
Parietal  and  visceral  anastomosis 
in  abdominal  wall,  248 

eminence,  4 

fissures,  21 

foramen,  10 

lobes  of  brain,  21 
Paronychia,  425 
Paroophoron,  283 
Parotid  abscess,  90 

opening  of,  91 

capsule,  116 

cyst,  92 

duct,  91 

fascia,  89 

fistula,  91 

gland,  89 

processes  of,  90 
inflammation  of,  91 
nerve-supply  of,  91 

recess,  89 

region,  89 

structures  within  the  gland,  90 

tumour,  91 

wounds,  91 
Parovarium,  282 

cysts  of,  283 
Parrot's  nodes,  2 
Pars  ciliaris  retinae,  68 

iridica  retinae,  68 
Patella,  335 

absence  of,  338 

blood-supply  of,  335 

development  of,  335 

dislocations,  337 

floating,  343 

fractures,  337 

ossification  of,  335 

surface  anatomy  of,  335 
Patellar  fossa,  69,  70 

ligament,  336 

plexus,  332 


Pelvic  arch,  249 

bones,  250 

cavity,  251 

cellulitis,  253,  276 

diaphragm,  151 

fascia,  251 

fatty  tissue,  253 

fossae,  253 

peritoneum,  253 

peritonitis,  276,  281 

symphysis,  250 

viscera,  253 
Pelvis,  249 

false,  251 

floor  of,  151 

fracture  of,  250 

of  kidney,  245 

true,  251 

vessels  of,  256 

viscera  of,  253 
Penis,  body  of,  265 

glans,  265 

malformations  of,  266 

nerves  of,  267 

root  of,  265 

suspensory  ligament  of,  265 

vessels  of,  267 
Perforating    ulcer    of   duodenum, 

211 

of  foot,  357 
of  stomach,  207,  203 
Pericardium,  effusion  into,  163 

fibrous,  161 

paracentesis  of,  163 

relations  of,  161 

to  chest-wall,  163 

serous,  162 

surgery  of,  163 
Pericardotomy,  164 
Pericranium,  8,  5,  9 
Perimetritis,  276 
Perineal  abscess,  286,  288 

body,  268,  279,  293 

fistula,  286 

hernia,  199,  202 

lithotomy,  287 
Perinephric  abscess,  245 
Perineum,  284 

anal  triangle  of,  289 

boundaries  of,  285 

central  point  of,  286 

fasciae  of,  285 

female,  288 

nerves  of,  286 

rectal  triangle  of,  285 

rupture  of,  289 

uro-genital  triangle  of,  285 

vessels  of,  286,  289 


INDEX 


467 


Periosteum  of  long  bones,  342 

function  of,  342 
Peripatellar  depression,  328 
Peritoneal  cavity,  201 

ligaments,  200 
Peritoneum,  200,  195 

duodenal  fossa  of,  213 

greater  sac  of,  200 

inguinal  sac  of,  190 

intersigmoid,  225 

ligaments  of,  200 

pararectal,  254,  291 

paravesical,  253 

lesser  sac  of,  201 

mesentery  of,  201 

pelvic  fossae  of,  253 

omenta  of,  200  et  seq. 

sacs  of,  200 
Peritonitis,  214,  220 

bands  from,  214 

deformans,  214,  217 

pelvic,  276,  281 

pyogenic,  220 

tubercular,  214 
Peroneal  compartment,  348 

sulci,  345 
Pes  anserinus,  38 

cavus,  368 
Petit's  canal,  71 

triangle,  241,  180 
Petrosal  sinus,  14,  27 
Petro-squamosal  suture,  46 
Peyer's  patches,  215 
Phantom  tumour,  179 
Pharyngeal  aponeurosis,  no 

muscles,  no 

tonsil,  1 10 

Pharyngo-laryngeal  recess,  124 
Pharyngotomy,  in 
Pharynx,  109 

abscess  of,  in 

foreign  bodies  in,  1 10 

inflammation  of,-iio 

lateral  recesses  of,  no 

lymphatic  glands,  1 1 1 

mucous  membrane  of,  no 

pyriform  fossa  of,  1 10 

relations  of,  1 1 1 

supratonsillar  fossa  of,  108 

tumours  of,  1 1 1 
Phimosis,  266 
Phlebitis,  femoral,  311 
Phlebotomy,  407 
Phlegmasia  alba  dolens,  276 
Phthisis  bulbi,  67 
Pia-arachnoid,  17 
Pia  mater,  18 

choroid  plexuses  of,  18 


Pia  mater,  of  cord,  145 
Pigeon  breast,  1 5 1 
Piles,  294 

sentinel,  289 
Pillars  of  external  ring,  191 

of  fauces,  106 
Pineal  body,  23 
Pinna,  42 

congenital  defects  of,  42 

injuries  to,  42 

vessels  of,  42 

Pirogoff's  amputation,  371 
Plantar  arch,  361 

fascia,  357 

ligaments,  357,  364 

nerves,  373 

vessels,  360 

Plantaris  tendon,  rupture  of,  349 
Pleura,  168 

cohesion  of,  170 

in  neck,  136 

lowest  level  of,  169 

reflections  of,  169 

relations  of,  168 

surgery  of,  171 

wounds  of,  170 

Pleural  cavity,  effusion  into,  171 
paracentesis  of,  171 

sinuses,  168 
Plexus  gulae,  175 

vesico-prostatic,  268 
Plica  semilunaris,  57 

sublingualis,  102 
Plugging  nares,  79 
Pneumatocele,  54 
Pneumonectomy,  174 
Pneumothorax,  170 
Pneumotomy,  174 
Point,  auricular  or  meatal,  3 

Erb's,  442 

McBurney's,  221 

pre-auricular,  3 
I    Politzer's     method     of     inflating 

middle  ear,  48 
I   Pollock's     method     of     dividing 

palate  muscles,  108 
Polycoria,  66 
Polypus  of  nose,  77 
Polymazia,  160 
Polythelia,  160 
Pons  Varolii,  3 1 

lesion  in,  38 
Popliteal  abscess,  331,  333 

aneurism,  332 

bursae,  334 

embolism,  333 

fascia,  331 

glands,  333 

30—2 


468 


SURGICAL  ANATOMY 


Popliteal  nerves,  331 

space,  330 

triangles  of,  330 

vessels,  332,  333 

Portal  and  systemic  venous  sys- 
tems, 231 

artificial         communica- 
tions, 231 

normal  connecting  chan- 
nels, 231,  294 

circulation,  231 

obstruction,  231 

vein,  231 

Position  of  cardiac  valves,  165 
Post-nasal  adenoids,  no 
Post-pharyngeal  abscess,  90 
Posterior  chamber  of  eyeball,  69 

fossa  of  skull,  14 

palatine  canal,  106 

prostatic  pouch,  260 

region  of  neck,  114 

triangle  of  neck,  135,  114 
Pott's  disease  of  spine,  1 41 , j  5 1 ,  24 1 

fracture,  363,  352 

puffy  tumour,  17 
Pouch,  duodenal,  213 

of  Douglas,  275,  291 

of  Prussak,  45 

post-prostatic,  260 

recto-genital,  275 

recto-vaginal,  273 

recto-vesical,  257 
Poupart's  ligament,  180 
Pre-auricular  point,  3 
Precentral  convolution  of  brain,  20 
Pre-interparietal  bone,  3 
Prepatellar  bursa,  330 
Prepuce,  266 
Presbyopia,  70 

Precentral  convolution  of  brain,  20 
Premaxilla,  107 
Pretibial  bursa,  330 
Pretracheal  fascia,  1 1 6,  135 
Prevertebral  abscess,  117 

fascia,  1 1 6 
Processus  cochleariformis,  47 

vaginalis,  196 
Priapism,  288 
Procidentia  uteri,  275 
Proctodaeum,  296 
Prolapsus  ani,  295 

uteri,  275 

Promontory  of  cochlea,  46 
Pronation,  movement  of,  419 
Proptosis,  56 
Prostate,  267 

function  of,  269 

hypertrophy  of,  269 


Prostate  lymphatics,  268 

middle  lobe  of,  267 

nerves,  268 

size  of,  267 
Prostatectomy,  269 
Prostatic  abscess,  268 

capsules,  268 

catheter,  269 

ducts,  263 

plexus  of  veins,  268 

pouch,  260 

sinus,  263 

urethra,  263,  267 

utricle,  263 

veins,  268 
Prostatitis,  268 
Prussak,  pouch  of,  45 
Psoas,  abscess,  241 

sheath,  241 
Pterion,  3 
Pterygium,  58 
Pterygo-maxillary  fissure/  97 

fossa,  96 
Ptosis  of  upper  eyelid,  56 

of    abdominal    viscera,    207, 

214,  227,  238 
Pubic  dislocation  of  hip,  318 

spine,  305 

Pudendal  hernia,  199 
Pulmonary  abscess,  173 

apoplexy,  173 

ligament,  169,  173 

valve,  164 

vessels,  173 
Pulp  of  fingers,  426 
Pulse,  double,  421 

radial,  414 

Punctum  lachrymale,  59 
Pupil,  65,  72 

Argyll-Robertson,  72 

causes  of  contraction  and  di- 
latation of,  72 

mechanism  of,  72 

nerve-supply  of,  72 
Pyelitis,  245 
Pylorectomy,  209 
Pyloric  antrum,  205 

canal,  205 

sphincter,  208 

tumours,  208 

valve,  205,  208 

vestibule,  205 
Pyloroplasty,  209 
Pylorus,  205 

altered    position    of,    in    dis- 
ease, 207 

congenital  tumour  of,  208 

dilatation  of,  209 


INDEX 


469 


Pylorus,  function  of,  208 

resection  of,  209 

stricture  of,  208 
Pyonephrosis,  245 
Pyosalpinx,  281 
Pyramid,  32,  47 
Pyramidal  lobe  of  thyroid,  130 

tracts,  32 

Pyriform  fossa  of  pharynx,  no 
of  larynx,  1  24 

Quadrilateral     space     of     axilla, 


Radical  cure  of  hernia,  198,  199 
Radio-carpal  joint,  432 
Radio-ulnar  joint,  inferior,  418 

superior,  410 
Radius,  416 

Colles's  fracture  of,  420 

dislocation  of,  413 

epiphysis  of,  421 

fractures  of,  419 

head  of  ,  409,  412 

nutrient  vessel  of,  416 

sarcoma  of,  420 

styloid  process  of,  42  1 
Ranula,  102 

Receptaculum  chyli,  217 
Recess,  internal  branchial,  137 

lateral,  124 

parotid,  89 

pubic,  289 
Rectal  ampulla,  290 

cystocele,  261 

epithelioma,  296 

examination,  291 

excision,  296 

fistula,  297 

prolapse,  295 

sinuses,  293 

triangle,  289 

valves,  290 
Rectocele,  279,  289 
Recto-genital  pouch,  275 
Recto-vaginal  fistula,  279 
septum,  279 
Recto-vesical  fascia,  251 

pouch,  257,  291 
Rectum,  290 

absent,  296 

absorptive  power  of,  298 

attachments  of,  290 

bands  of,  290 

carcinoma,  296 

curves  of,  290 

deformities  of,  290 

development  of,  295 


Rectum,  effects  of  distension  of,  290 

excision  of,  296 

fissure  of,  297 

fistula  of,  297 

introduction  of  hand  into,  293 

of  child,  295 

Kraske's  sacral  resection  of, 
296 

ligaments  of,  292 

lymphatics  of,  294 

methods   of   examination   of, 
290,  291,  292 

nerves  of,  294 

peritoneum  of,  291 

polypus,  292 

pouch  of,  291 

prolapse,  295 

stricture  of,  293,  296 

tumours  of,  292 

valves  of,  293 

vessels  of,  293 

Referred  pain,  155,  184,  206,  221, 
224,  233,  235,  245,  260,  268, 
273,  288,  295,  302,  316,  320, 

345.  357 

Reil,  island  of,  22 
Renal  abscess,  245 

calculus,  245 

colic,  245 

haemorrhage,  245 
Respiration    in    fractured    spine, 

148 

Restiform  body,  32 
Retained  testicle,  273 
Retention  of  menses,  284 

of  urine,  295 
Retina,  68 

detachment  of,  69 

f ovea  centralis  of,  69 

glioma  of,  69    • 

inflammation  of,  69 

optic  disc  of,  68 

ora  serrata  of,  68 

pars  ciliaris  of,  68 
iridica  of,  68 

structure  of,  68 
Retinitis,  69 

Retroflexion  of  uterus,  275 
Retroperitoneal  abscess,  241 
hernia,  213 

Retropharyngeal  abscess,  in 
Retropubic  fat,  259 
Retroversion  of  uterus,  275 
Rhinitis,  atrophic,  76 

hypertrophic,  76 
Rhinoliths  of  nose,  80 
Rhinoplasty,  74 
Rhinoscopy,  80 


470 


SURGICAL  ANATOMY 


Ribs,  152 

accessory,  152 

cervical,  152 

enumeration  of,  152 

fractures  of,  152 

insane,  153 

resection  of,  154 

rickets  of,  153 

tubercle  of,  153 
Richter's  hernia,  198 
Rickets  of  femur,  326 

of  pelvis,  250 

of  ribs,  153 

of  skull,  9 

of  tibia,  351 
Rider's  bone,  311 

sprain,  310/31 1 
Riedel's  lobe,  228 
Rima  glottidis,  125 
Ring,  abdominal,  191,  189 

crural,  193,  309 
Risus  sardonicus,  93 
Rivini,  duct  of,  102 
Rodent  ulcer,  55,  85 
Rolandic  area,  20 
Rolando,  fissure  of,  4 

tubercle  of,  32 
Root  of  lung,  173 

of  penis,  265 
Rosenmiiller,  fossa  of,  no 

organ  of,  282 
Rose's  operation,  99 
Rouge's  operation,  80 
Round  ligament  of  liver,  230,  186 
of  uterus,  283 

shortening  of,  283 
Rupture  of  biceps,  396 

of  urethra,  264,  287 

Sac,  lachrymal,  59 
Sacral  dermoids,  250 
nerves,  371 
tumour,  250 
Sacro-coccygeal  joint,  251 

dislocation  of,  251 
region,  250 

tumours  of,  251 
S aero-genital  fold,  253,  257 
Sacro-iliac  joint,  250 

disease  of,  250 
Sacro-sciatic  foramina,  304 

ligaments,  304 
Sacro-vertebral  angle,  140 
Sacrum,  section  of,  Bardenheuer, 

297 

Kraske,  296 
Sagittal  fontanelle,  4 
section,  2 


Sagittal  suture,  2 
Salivary  cyst,  92 

fistula,  92 
Salmon  patch,  65 
Salpingitis,  281 

Salpingo-pharyngeal  folds,  109 
Santorini,  duct  of,  236 

fissures  of,  43 
Saphenous     opening,      193,     306, 

308 

Scalene  tubercle,  136 
Scalp,  5 

abscess  of,  8 

avulsion  of,  6 

cephalhaematoma,  8 

cirsoid  aneurism  of,  7 

dangerous  area  of,  8 

effusions  in,  8 

haemorrhage  from,  7 

haematoma  of,  8 

lymphatics  of,  7 

mobility  of,  5 

nerves  of,  7 
•  neuralgia  of,  7 

sebaceous  cysts  of,  5 

temporal  region  of,  9 

vessels  of,  6,  7 

wounds  of,  7,  8 

Scaphoid  bone,  dislocation  of,  367 
Scapula,  acromion  process  of,  381 

excision  of,  382 

fracture  of,  381 

luxation  of,  381 

surgical  neck  of,  382 
fracture  of,  382 

tumours  of,  382 
Scapular  region,  381,  377 

spine,  377 
Scarpa's  fascia,  285 

triangle,  305 

fascia  of,  306 
glands  of,  306 
superficial  anatomy  of, 

305 
surgical     affections      of, 

305.  306 
vessels  of,  306 
Schlemm,  canal  of,  64 
Schneiderian  membrane,  76 
Sciatic  dislocation,  318 

hernia,  304 
Sciatica,  302 
Scirrhus  mammae,  159 
Sclerotic,  64 
Scoliosis,  140,  151 
Scrotum,  274 

development  of,  274 
elephantiasis  of,  274 


INDEX 


471 


Scrotum,  integuments  of,  274 

lymphatics  of,  274 

nerves  of,  274 

oedema  of.  274 

septum  of,  274 

vessels  of,  274 
Seat  of  election,   amputation   at, 


353 
jbc 


Sebaceous  cyst,  5 
Semilunar  cartilage  of  knee,  339 
dislocation  of,  339 

fold  of  Douglas,  180 
Semicircular  canals,  54,  48 
Seminal  vesicles,  269 
Sensory  tract  in  cord,  33 
Sentinel  pile,  298 
Septum  crurale,  193 

lingual,  105 

of  nose,  75 

orbital,  57 

pectiniforme  of  penis,  265 
Sesamoid  bones,  437 
Sheath,  carotid,  132 

femoral,  309,  191 

of  rectus  abdominis,  179 
Shingles,  155 
Shoulder,  375 

clavi-pectoral  region  of,  377 

deltoid  region  of,  376 

dislocation  of,  385 
tests  for,  385 

fractures  about,  381,  400 

girdle,  377 

joint,  383 

amputation  at,  388 
disease  of,  387 
excision  of,  387 
luxation  of,  385 

surface  anatomy  of,  375 
Shrapnell's  membrane,  45 
Sigaultean  operation,  250 
Sigmoid  cavity  of  ulna,  409 

flexure,  224 

sinus,  27 

thrombosis,  51 
Sinus,  accessory,  of  nose,  80 

cavernous,  27 

thrombosis  of,  61 

circular,  27 

frontal,  82,  10 

great  transverse,  163 

inferior  petrosal,  27 

lateral,  27,  4 

longitudinal,  tears  of,  12 

petrosal,  14 

pleural,  168 

pocularis,  263 

pyriform,  of  larynx,  124 


Sinus,  pyriform,  of  pharynx,  1 10 
sigmoid,  27 

aspiration,  prevention  of, 

28 

thrombosis  of,  28 
sphenoidal,  81 
straight,  28 
superior  longitudinal,  26 

nsevi     connected     with, 

27 

thrombosis  of,  27 
transverse,     of    pericardium, 

163 

Skey's  amputation,  370 
Skin,  bronzing,  247 
Skull,  abnormalities  of,  i 

base  of,  12 

brachycephalic,  i 

craniotabes  of,  9 

development  of,  9,  12 

diploic  tissue  of,  10 

dolichocephalic,  i 

emissary  veins  of,  10 

fractures  of,  10,  n,  14 

gunshot  wounds  of,  9 

necrosis  of,  9 

of  infant,  1 1 

rickets  of,  i 

soft  parts  covering,  5 

sutures  of,  1 1 

syphilis  of,  i 

tables  of,  9 

thickness  of,  10 

vault  of,  9 

vessels  of,  10,  16 
Small  intestine,  214 

trochanter,  314 
Smith's  amputation,  344 
Snuffles,  75 
Socia  parotidis,  90 
Soft  palate,  106 
Solar  plexus,  247,  248 
Sole  of  foot,  354 
Spasmodic  stricture  of  oesophagus, 

175 

torticollis,  119,  41 
Spermatic  cord,  271 
Spermatocele,  271 
Spermatorrhoea,  292 
Spheno-maxillary  fissure,  97 

fossa,  99 

Spheno-palatine  foramen,  97 
Sphenoidal  fissure,  97 
sinus,  8 1 

ostium  of,  8 1 

Spigelian  lobe  of  liver,  228 
Spina  bifida,  145 

occulta,  145 


472 


SURGICAL  ANATOMY 


Spinal  cord,  143 

length  of,  143 
relations  of,  143 
concussion,  145 
crush,  146 

'  injuries,  145,  146 

lesions,  localization  of,  146 

meninges,  144 

meningitis,  144 

nerves,  146 

points  of  emergence  of,  147 

operations,  149 

vessels,  143,  145 

wounds,  146 
Spine,  caries  of,  141 

curves  of,  140 

fracture  dislocations  of,  142 

nasal,  106 

of  Henle,  52 

of  pubis,  305 

scoliosis  of,  140 

sprains  of,  141 

Spinous  processes,  fracture  of,  143 
Spleen,  237 

abscess  of,  238 

accessory,  237 

ague  cake,  238 

capsule  of,  237 

dislocation  of,  238 

enlarged,  238 

extirpation  of,  238 

hilum  of,  237 

injuries  to,  238 

in  leucocythaemia,  238 

lymphatics  of,  238 

nerves  of,  238 

notches  of,  237,  238 

position  of,  238 

relations  of,  237 

rupture  of,  238 

supporting  mechanism  of,  237 

vessels  of,  237 

wandering,  238 
Splenectomy,  239 
Splenic  flexure,  223 
Splenopexy,  239 
Spondylolisthesis,  140 
Spongy  urethra,  263 
Sprains  of  spine,  141 

of  ankle,  358,  362 
Staphylorrhaphy,  108 
Stenotic  gastrectasis,  206 
Stenson's  duct,  91,  100 
cyst  of,  92 
fistula  of,  92 
Stercoral  ulcer,  218 
Sternal  angle,  1 5 1 

notch,  150 


Sterno-clavicular  joint,  378 
disease  of,  379 
dislocations  of,  378 
movements  of,  378 
Sterno-mastoid  region,  113 

muscle,  tenotomy  of,  119 

tumour,  119 
Sternum,  151 

apertures  in,  152 

depressions  in,  152 

fractures  of,  151 

injuries  of,  152 

separation  of  segments  of,  151 

trephining,  152 
Stilling,  hyaloid  canal  of,  71 
Stomach,  203 

body  of,  205 

cardia  of,  203 

contraction  of,  206 

cough,  41 

curvatures  of,  203 

dilatation  of,  206 

displacement  of,  207 

foreign  bodies  in,  208 

fuiidus  of,  204 

hour-glass  contraction  of,  207 

level  of,  204 

lymphatics  of,  206 

nerves  of,  206 

notch  of,  204 

operations  on,  207 

perforation  of,  207 

pylorus  of,  205,  208 

ptosis  of,  207 

relations  of,  205 

space  in  abdomen  containing, 
205 

tumours  of,  207 

ulceration  of,  207 

wounds  of,  208 

vessels  of,  205 
Stone  in  bladder,  261 

in  kidney,  245 
Strabismus,  60 

Strangulation  in   femoral   hernia, 
198 

in  inguinal  hernia,  198 

in  obturator  hernia,  195 

internal,  203 
Striae  acousticae,  31 
Stratum  vasculosum,  67 
Stricture  of  oesophagus,  175 

of  urethra,  264 
Student's  elbow,  408 
Stump  neuroma,  328 
Stye,  55 

Styloid   processes   of   radius    and 
ulna,  421.  422 


INDEX 


473 


Stylo-mastoid  foramen,  38 
Subacromial  bursa,  383 

disl  >cation  of  humerus,  387 
Subarachnoid  space,  18,  144 
Subastragaloid  dislocation,  367 
Subclavian  artery,  ligature  of,  136, 

138 

triangle  of  neck,  135 
Subclavicular  dislocation  of  shoul- 
der, 386 

fossa,  375 

Subcoracoid  dislocation  of  shoul- 
der, 386 

Subconjunctival  haemorrhage,  57 
Subdeltoid  bursa,  383 
Subdural  haemorrhage,  18 

space,  17,  144 

Subglenoid  dislocation  of  shoulder, 
,  386 

Sublingual  gland,  102 
Submaxillary  abscess,  122 
capsule,   116 
glands,  122 
region,  121 
salivary  glands,  105 
Submental  triangle,  121 
Submesocolic  compartment  of  ab- 
domen, 202,  212 
Subperitoneal  tissue,  182 
Subphrenic  abscess,  207 
Subspinous  dislocation   of  shoul- 
der, 387 

Sucking-pad,  85 
Sulci  of  brain,  relations  of,  20 
Superficial  cardiac  area,  163 
cervical  glands,  122,  132 
palmar  arch,  430 
Superior  longitudinal  sinus,  26 
maxilla,  88 

excision  of,  89 
fractures  of,  88 
tumour  of,  89 
vena  cava,  165,  160- 
Supernumerary  mamma,  160,  306   ; 
Supination,  movement  of,  419 
Supraclavicular  fossa,  114 

region,  135 
Supracondyloid  lymphatic  gland,    ! 

395 

process,  398 

Suprameatal  triangle,  52 
Supramesocolic    compartment    of 

abdomen,  205 
Supra-orbital  foramen,  54 

notch,  4 

Suprapubic  cystotomy,  262 
Suprarenals,  246 
Suprasternal  notch,  1 50 


Supratonsillar  fossa,  108 
Surgical  affections  of  long  bones, 
341,  402 

kidney,  245 

neck  of  humerus,  399 

of  scapula,  382 
Suture  of  skull,  1 1 

closure  of,  1 1 

coronal,  2 

foatal,  3 

lambdoidal,  2 

masto-squamosal,  53 

occipital,  3 

petro-squamosal,  46 

relations  of,  to  surface,  2 

sagittal,  2 

separation  of,  1 1 
Sylvius,  aqueduct  of,  24 

fissure  of,  4,  19 
Symblepharon,  57 
Syme's  amputation,  370 
Sympathetic  ophthalmia,  67 
Symphysis  pubis,  250 
Synechia,  anterior,  65 

posterior,  67 
Synostosis  of  skull,  1 1 
Synovial  sheaths  of  foot,  358 

of  hand,  428 
Syphilis  of  bone,  i,  351,  402 

of  testicle,  273 

of  tongue,  105 
Syringomyelocele,  145 

Tabatidre  anatomique,  422 
Tabes  mesenterica,  217 
Tagliacozzi's  operation,  395,  74 
Talipes,  367 

calcaneus,  368 

cavus,  357,  368 

equino-varus,  367 

equinus,  368 

valgus,  368 

varus,  368 
Tapping  bladder,  258 

lateral  ventricles,  25 

pericardium,  163 

pleura,  153 
Tarsal  bones,  366 

fractures     and     disloca- 
tions of,  366 

cartilages,  54 

cysts,  55 

joints,  364 

ligaments,  56 
Tarsectomy,  369 
Tarso-metatarsus,  365 
Tarsus,  364 
Taxis,  194 


474 


SURGICAL  ANATOMY 


Teale's  amputation,  353 
Teeth,  94 

development  of,  95 

extraction  of,  95 

roots  of,  95 

syphilis  of,  95 

supernumerary  incisor,  107 

time  of  eruption  of,  94 

tumours  of,  95 
Tegmen  antri,  48 

tympani,  46 
Tegmentum,  30 
Temporal  abscess,  9 

bone,  44 

fascia,  9 

lobes  of  brain,  21 

muscle,  9 

region,  9 

Temporo-maxillary     articulation, 
92 

anchylosis  of,  93 

capsule  of,  93 

disease  of,  93 

dislocation  of,  93 

excision  of,  93 
Temporo-sphenoidal  lobe,  21 

abscess  of,  21 
Tendo  Achillis,  349 

tenotomy  of,  355 

oculi,  57 

Tendon,  conjoined,  180 
Tendons  of  ankle,  358 

of  wrist,  431 
Tenon's  capsule,  62 
Tenotomy  of  biceps  femoris,  334 

of  hamstrings,  334 

of  sterno-mastoid,  1 1 9 

of  tendo  Achillis,  355 

of  tibialis  anticus,  358 

of  tibialis  posticus,  358 
Tentorium,  14,  17 
Testicle,  272,  195 

descent  of,  195 

injury  to,  273 

inversion  of,  274 

lymphatics  of,  273 

mediastinum  of,  272 

nerves  of,  273 

pathological  conditions  affect- 
ing, 273 

retained  or  undescended,  273 

tunics  of,  272 

vessels  of,  273 
Thalami,  optic,  23 
Thecal  abscess,  428 
Thenar  eminence,  426 
Thigh,  322 

amputation  of,  327 


Thigh,  fasciae  of,  323 

septa  from,  323 
fractures  of,  325 
integuments  of,  323 
muscles  of,  323 
surface  anatomy  of,  322 
Third  ventricle,  24 
Thomas's  incision  for  removal  of 

breast  tumours,  160 
Thoracic  aneurism,  167 
aorta,  166 
cavity,  160 
duct,  249 

Thoracoplasty,   172 
Thoracotomy,  153 
Thorax,  150 

deformities  of,  150 
nerves  of,  155 
paracentesis  of,  153 
skin  of,  1 50 

surface  anatomy  of,  1 50 
tumours  of,  157,  167,  174 
vessels  of,  164,  150 
viscera  of,  164 
walls  of,  152 
wounds  of,  165 
Thrombosis,  infective,  26 

marasmic,  27 
Thumb,  436 

amputation  of,  437 
Hey's  dislocation  of,  437 
Thymus  gland,  130,  161 
Thyro-glossal  duct,  102,  103 
Thyro-hyoid  bursa,  123 
membrane,  123 
Thyroid  cartilage,  126 
cysts,  131 

dislocation  of  hip,  318 
gland,  128 

accessory,  131 
development  of,  131 
excision  of,  130 
in  tracheotomy,  128 
isthmus  of,   130 
lobes  of,  128 
lymphatics  of,  130 
nerves  of,  130 
relations  of,  129 
vessels  of,  129,  130 
Thyroidectomy,  130 
Thyrotomy,  126 

Tibia,  cuneiform  osteotomy  of,  352 
fractures  of,  351 
head  of,  341 
injuries  to,  352 
nutrient  foramen  of,  351 
osteomyelitis  of,  351 
rickets  of,  351 


INDEX 


475 


Tibia,  sarcoma  of,  341 

syphilitic  disease  of,  351 

tubercle  of,  341 

vessels  of,  351 
Tic-douloureux,  37,  87 
Toes,  369 
Tongue,  102 

dermoid  of,  103 

epithelioma  of,  105 

excision  of,  105 

fissures  of,  103 

foramen  caecum  of,  103 

functions  of,  102 

furred,  103 

lymphatics  of,  104 

muscles  of,  104 

nerve-supply  of,  104 

paralysis  of,  105 

septum,  105 

strawberry,  103 

tie,  103 

tumours  of,  103 

ulcers  of,  105 

vessels  of,  103 
Tonsil,  1 08 

abscess  of,  109 

bleeding  from,  108 

calculi  in,  109 

hypertrophy  and  deafness,  1 09 

lingual,  103 

Luschka's,  no 

lymphatics  of,  108 

pharyngeal,  1 10 

tumours  of,  109 

vessels  of,  108 
Tonsillitis,  109 
Tonsillotomy,  108 
Torcular  Herophili,  26 
Torticollis,  1 18,  41 
Torus  uterinus,  283 
Trachea,  127 

foreign  bodies  in,  168 

relations  of,  127 

thoracic,  168 
Tracheal  tugging,  167 
Tracheotomy,  128 
Trachoma,  58 
Tracts  of  cord,  32 
Transversalis  fascia,  182,  189,  191 
Transverse  colon,  223 

humeral  ligament,  385 

sinus,  163 
Trapezium,  433 
Treitz,  ligament  of,  211 
Trendelenburg's  operation,  250 
Trephining  for  middle  meningeal 
artery,  26 

for  intracranial  lesions,  34 


Triangle,  Bryant's,  300 

carotid,  112 

digastric,  121 

infrahyoid,  112,  123 

Jingual,  122 

of  Petit,  1 80,  241 

of  Scarpa,  305 

occipital,  136 

rectal,  285 

subclavian,  135 

submaxillary,   1 1 2 

submental,  121 

suprameatal,  52 

urogenital,  285 
Triangles  of  neck,  112,  120 
Triangular  fascia  of   Colles,    285, 
178,  265 

fibre-cartilage  of  wrist,  418 

ligament  of  urethra,  286 
Trichiasis,  55 
Tricuspid  valve,  165 
Trigones  of  bladder,  259 
Trigonum  femorale,  255 
Trismus,  93 
Trochanters,  314 

bursae  of,  301 

fossa  of,  300 

fracture  of,  313 
Trochlea,  409 

Tropical  abscess  of  liver,  233 
Tubal  pregnancy,  281 
Tube,  Eustachian,  47,  109 

Fallopian,  280 
Tuber  ischii,  300 
Tubercle  adductor,  329 

deltoid,  375,  399 

of  Chassaignac,  133 

of  Darwin,  42 

of  Lisfranc,  136 

of  Rolando,  32 

of  tibia,  341 

scalene,  136 

Tumour,  Pott's  puffy,  17 
Tunica  albuginea,  265,  272 

vaginalis,  197,  272 
Turbinal  bones,  77 
Tympanic  antrum,  45 

attic,  45 

membrane,  44 

incision  of,  45 
rupture  of,  45 

ossicles,  45 

promontory,  46 
Tympanum,  45 

attic  of,  45 

boundaries  of,  45 

infection  of  and  spread  from, 
48,  50 


476 


SURGICAL  ANATOMY 


Tympanum,    mucous    membrane 

of,  45 

muscles  of,  47 
nerves  of,  47 
pyramid  of,  47 
relation  of  facial  nerve  to,  46 
roof  of,  46 
vessels  of,  47 

Ulcer,  duodenal,  211 
of  stomach,  207 
stercoral,  218 
Ulna,  416 

dislocation  of,  413 
fracture  of,  419 
nutrient  vessel  of,  416 
ridge  of,  414 

styloid  process  of,  421,  422 
upper  extremity  of,  409 
Umbilical  canal,  187 
cord,  185 
fistula,  1 86 
hernia,  acquired,  187 
congenital,  186,  187 
infantile,  187 
loop,  1 86 

notch  of  liver,  229 
region,  177 
ring,  185 
vesicle,  186 
Umbilicus,  185,  178 

fibrous  ring  of,  186 
fistulas  at,  1 86,  187 
vessels  of,  186 

Umbo  of  membrana  tympani,  44 
Uncinate  process  of  ethmoid,  78 

of  pancreas,  235 
Undescended  testicle,  273 
Upper  extremity,  375 
jaw,  88 

excision  of,  89 
fracture  of,  88 
tumours  of,  89 
Urachus,  186 
Uranoplasty,  108 
Ureter,  abdominal,  247 
distension  of,  247 
implantation  of,  248 
pelvic,  male,  253 

female,  284 
pelvis  of,  245 
relations  of,  247 
rupture  of,  248 
vaginal  palpation  of,  284 
wounds  of,  247 
Urethra,  curves  of,  262 
false  passages  in,  264 
female,  262 


Urethra,  fossa  navicularis  of,  263 

male,  262 

membranous,   263 

narrowest  parts  of,  264 

nerve-supply,  265 

prostatic,  263 

rupture  of,  264,  287 

spongy  portion  of,  263 

stricture  of,  263 

gonorrhceal,  264 

syphilitic,  264 

traumatic,  264 
Urethral  car  ancle,  262 
Urinary  fistula,  187 
Urine,  extravasation  of,  264,  287 

incontinence  of,  297 
Urogenital  sinus,  266 
space,  285 

Utero-sacral  folds,  253 
Uterus,  275 

arbor  vitae  of,  276 

bicornis,  279 

body  of,  275 

broad  ligaments  of,  279 

carcinoma  of,  276 

cavity  of,  276 

cervix  of,  275 

development  of,  279 

external  os  of,  275 

flexion  of,  275 

fundus  of,  275 

inflammation  of,  276 

interior  of,  276 

internal  os,  275 

lymphatics  of,  277 

nerves  of,  277 

operations  on,  276 

peritoneum  of,  275 

prolapse  of,  275 

relations  of,  276 

retroversion  of,  275 

surgical  affections  of,  276 

vessels  of,  276 
Uveal  tract,  65 
Uvula  vesicae,  260 

Vagina,  277 

dilatability,  279 

fornices  of,  278 

lymphatics  of,  279 

nerves  of,  279 

relations  of,  279 

rugae  of,  277 

sphincter  of,  279 

vessels  of,  279 

walls  of,  279 
Vaginal  cystocele,  261,  279 

cystotomy,  262 


INDEX 


477 


Vaginal  enterocele,  279 
nstulae,  261 . 
foraices,  278 
hernia,  279 
process,  196 
Vaginismus,  279 
Valsalva,  sinus  of,  166 
Valsalva's  method  of  inflating  the 

middle  ear,  48 
Valve,  ileo-caecal,  221 

function  of,  222 
Valves,  anal,  293 
of  heart,  164 
rectal,  of  Houston,  290 
Valvulae  conniventes,  215 
Varicocele,  272 
Varicose  veins,  346 

cause  of  pain  in,  345 
Vasa  efferentia,  271 
Vas  aberrans  of  arm,  398 
deferens,  270 

ampulla  of,  270 
artery  of,  271 
palpation  of,  271 
Vater,  ampulla  of,  235 
Vault  of  skull,  fracture  of,  1 1 
Veins.     See  Various  regions 
angufcir,  86 
axillary,  392 
azygos,  161 
basilic,  397,  405 
brachial,  397 
cava  inferior,  248 
superior,  165 
cephalic,  377,  405 
of  thumb,  422 
coronary,  206 
diploic,  10 
dorsal,  of  penis,  266 
emissary,  of  skull,  10 
epigastric,   1 79 
facial,  86 
femoral,  311 
haemorrhoidal,  293 
hepatic,  232 
iliac,  256 
innominate,  377 
intercostal,  154 
internal  saphenous,  194 
jugular,  anterior,  113 
external,   113 
internal,  135 
long  saphenous,  306,  311,  323 

thoracic,  391 
mastoid,  10,  28 
median,  405 

basilic,  397,  407 
cephalic,  405 


Veins,  mesenteric,  216,  226 

nasal,  77 

of  foramen  caecum,  10 

of  Galen,  28 

ophthalmic,  72 

orbital,  10 

pampiniform  plexus,  272 

para-umbilical,  179 

parietal,  10 

popliteal,  333 

portal,  231 

prostatic  plexus,  267 

pterygoid  plexus,  98 

radial,  414 

ranirie,  103,  122 

renal,  244 

Salvatella,  425 

short  saphenous,  331 

spermatic,  272 

splenic,  238 

subclavian,  378 

thoracico-epigastric,  179 

thyroid,  130 

uterine,  276 

utero- vaginal  plexus,  277 

ulnar,  414 

umbilical,  179 

vertebral,  143 

vorticosae,  72 
Veins,  air  in,  135,  391,  392 

canalized,  391 

circulation  in,  346 

emissary,  of  skull,  10 

of  neck,  wound  of,  135 
Velum  interpositum,  18 
Venesection,  407 
Venous      plexus,      pampiniform, 

272 

prostatic,  267 
pterygoid,  98 
utero-vaginal,  277 
Ventral  hernia,  178,  221 
Ventricles  of  brain,  24,  3 1 

of  larynx,  125 
Vermiform  appendix,  218 
abscess  of,  22 1 
coproliths  of,  220 
foreign  bodies  in,  220 
function  of,  220 
gangrene  of,  220 
inflammation  of,  220 
lymphatics  of,  220 
mesentery  of,  219 
nerves  of,  220 
operations  on,  220 
pathological  changes  in, 

220 
structure  of,  219 


478 


SURGICAL  ANATOMY 


Vermiform  appendix,  valve  of,  219 

function  of,  220 
variations  in  position  of, 

219 

vessels  of,  219 
Vermis  of  cerebellum,  30] 
Vertebra,    aneurismal   erosion   of, 

141 

caries  of,  141 
prominens,  112 
Vertebral  aponeurosis,  239 
column,  139 

fracture    dislocation    of, 

142 

sprains  of,  141 
bodies,  141 
curves,  140 
discs,  141 
Vertex  of  skull,  3 
Verumontanum,  260,  263 
Vesicocele,  279 
Vesicle,  umbilical,  186 
Vesico-vaginal  fistula,  261 
Vesiculi  seminales,  269 

inflammation  of,  270 
Vestibule  of  larynx,  125 
of  mouth,  100 
of  nose,  76 

Visceroptosis.    See  Various  organs 
Vitello-intestinal  duct,  186 
Vitreous  humour,  70 

affections  of,  71 
fossa  patellaris  of,  69,  70 
hyaloid,  canal  of,  7 1 

membrane  of,  70 
Vocal  cords,  125 
Volvulus,  225 
Vulva,  284 

Wardrop's  operation,  133 
Water-bed  of  brain,  18 


Weaver's  bottom,  302 

eye,  72 
Wen,  5 
Wharton's  duct,  102 

jelly,  187 
White  line  at  anus,  293 

of  pelvic  fascia,  251 
Whitlow,  426 
Wilde's  incision,  53 
Willis,  circle  of,  28 
Winslow,  foramen  of,  201 

ligament  of,  338 
Wirsung,  duct  of,  236 
Wolffian  ducts,  266 
Word-hearing  centre,  21 
Word-seeing  centre,  21 
Wormian  bones,  11,2 
Wrist,  421 

drop,  439 
joint,  432 

amputation  at,  435 
dislocation  of,  434 
excision  of,  434 
ligaments  of,  431 
movements  at,  434 
synovial  cavities  of,  433 
surface  anatomy  of,  421 
tendons  of,  431 
Wry -neck,  118 

Y-shaped  ligament  of  femur,  3 1 5 
cartilage  of  acetabulum,  312 
Yolk-sac,  1 86 

Zona  ophthalmica,  65 

orbicularis  of  eyeball,  66 
of  hip,  314 

Zonule  of  Zinn,  70 

Zygoma,  fracture  of,  98 

Zygomatic  abscess,  97 
fossa,  96 


THE    END 


Bailliere,  Tindall  and  Cox,  %,  Henrietta  Street,  C event  Garden 


THE  LIBRARY 
UNIVERSITY  OF  CALIFORNIA 

San  Francisco  Medical  Center 
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14  DAY 

DEC  16. 1969 

RETURNE 

DECl2l9d9 


20m-4,160(B171«4)4128 


132838 


